From 3a66c39f4852aa4c496002f5ac5dbbc9d7f04f98 Mon Sep 17 00:00:00 2001
From: Jesse_Chen <chen.yue@mevixaga.com>
Date: Sat, 26 Sep 2026 19:23:52 +0800
Subject: [PATCH] refactor(rectification): split the chat component into hooks,
 parameter functions and blocks
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Move-only (TASK-rectification-code-split-20260926 T1/T4). No behavior, API,
copy, DB, Skill or scoring change.

- rectification-agentic-chat.tsx: 2043 -> 737 lines; component body
  1625 -> 630; useState 35 -> 12, useRef 16 -> 9, effects 9 -> 5,
  useCallback 12 -> 6.
- Snapshot sync -> hooks/use-rectification-case-snapshot.ts; board layout
  and live label clock -> two small hooks.
- send / submitStructuredChoice / acceptCandidate bodies ->
  lib/rectification-chat-{turn,choice,accept}-run.ts parameter functions
  (bodies verbatim, deps destructured to the same names); copy/regenerate,
  question repair, pure transcript and snapshot helpers and the per-render
  view derivation -> lib/rectification-chat-*.ts (no React hooks).
- Question-gap blocks and the read-only range line ->
  components/rectification-question-gap-notices.tsx.
- Dependency arrays kept exactly as before (lint warnings +3, listed in
  PROGRESS); no dep added to appease the linter.
- Tests: whole-source contracts read tests/rectification-chat-surface.ts
  (container + split files, like home-surface.ts); slices of moved code now
  call the extracted functions or render the extracted block, each with a
  原值/新值/原因 comment. New tests/rectification-growth-contract.test.ts.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017eEAG8HD3mm8gsKXgk8uU8
---
 frontend/DESIGN.md                            |    2 +-
 .../components/rectification-agentic-chat.tsx | 1754 +++--------------
 .../rectification-question-gap-notices.tsx    |  151 ++
 .../hooks/use-rectification-board-layout.ts   |   53 +
 .../hooks/use-rectification-case-snapshot.ts  |  211 ++
 .../hooks/use-rectification-live-activity.ts  |   66 +
 .../src/lib/rectification-chat-accept-run.ts  |  183 ++
 .../src/lib/rectification-chat-choice-run.ts  |  283 +++
 .../lib/rectification-chat-message-actions.ts |   88 +
 .../src/lib/rectification-chat-messages.ts    |  163 ++
 .../lib/rectification-chat-question-repair.ts |   99 +
 .../src/lib/rectification-chat-snapshot.ts    |   94 +
 .../src/lib/rectification-chat-turn-run.ts    |  510 +++++
 frontend/src/lib/rectification-chat-view.ts   |  291 +++
 .../account-dialog-inert-20260918.test.ts     |    4 +-
 .../tests/agent-voice-copy-contract.test.ts   |   10 +-
 frontend/tests/chat-composer-queue.test.ts    |   34 +-
 .../chat-notice-and-scroll-contract.test.ts   |    7 +-
 frontend/tests/chat-stream-layout.test.ts     |    7 +-
 frontend/tests/composer-ime-contract.test.ts  |    7 +-
 .../tests/composer-isolation-contract.test.ts |    7 +-
 .../tests/consultation-entrypoint.test.ts     |   10 +-
 .../rectification-activity-receipt.test.ts    |   65 +-
 ...fication-adopt-cards-stay-20260909.test.ts |   45 +-
 .../rectification-adopt-flow-20260902.test.ts |    7 +-
 ...tification-adopt-flow-fix-20260903.test.ts |   13 +-
 .../tests/rectification-agentic-entry.test.ts |  122 +-
 .../tests/rectification-answer-choice.test.ts |    4 +-
 .../tests/rectification-chat-run-fixtures.ts  |  361 ++++
 frontend/tests/rectification-chat-surface.ts  |   34 +
 ...tification-dead-d9-choice-20260916.test.ts |    7 +-
 ...tion-delivery-ui-simplify-20260908.test.ts |    4 +-
 ...tion-engine-version-cross-midnight.test.ts |    4 +-
 ...ification-exhaustion-exit-20260906.test.ts |   24 +-
 .../rectification-growth-contract.test.ts     |   88 +
 ...ification-occupation-coverage-exit.test.ts |    4 +-
 ...on-other-collect-fallback-20260908.test.ts |    4 +-
 ...ication-post-adopt-verify-20260904.test.ts |   39 +-
 ...ication-probe-replay-loss-20260908.test.ts |   26 +-
 .../rectification-question-in-message.test.ts |    4 +-
 .../rectification-question-ownership.test.ts  |    4 +-
 .../rectification-range-bar-20260916.test.ts  |    4 +-
 ...tification-range-delivery-20260907.test.ts |    7 +-
 ...rectification-settled-render-split.test.ts |    7 +-
 ...on-skipped-health-deadend-20260909.test.ts |    4 +-
 .../tests/rectification-spoken-answer.test.ts |    7 +-
 .../rectification-spoken-collect.test.ts      |   27 +-
 .../rectification-step-state-20260906.test.ts |    4 +-
 .../rectification-surface-contract.test.ts    |   36 +-
 ...cation-targeted-card-live-20260913.test.ts |    4 +-
 ...ted-spoken-focus-recovery-20260913.test.ts |    4 +-
 ...ification-tie-break-entry-20260913.test.ts |    4 +-
 ...cation-tiebreak-card-loss-20260915.test.ts |   40 +-
 .../rectification-timeline-20260909.test.ts   |   58 +-
 .../rectification-timeline-adapter.test.ts    |    4 +-
 .../rectification-unwritten-evidence.test.ts  |    7 +-
 ...tion-v10-focus-receipt-consistency.test.ts |    7 +-
 .../tests/rectification-v9-contracts.test.ts  |    4 +-
 .../rectification-varga-style-copy.test.ts    |    4 +-
 .../rectification-walkthrough-polish.test.ts  |    4 +-
 ...cation-year-focus-overlay-20260916.test.ts |    4 +-
 61 files changed, 3402 insertions(+), 1731 deletions(-)
 create mode 100644 frontend/src/components/rectification-question-gap-notices.tsx
 create mode 100644 frontend/src/hooks/use-rectification-board-layout.ts
 create mode 100644 frontend/src/hooks/use-rectification-case-snapshot.ts
 create mode 100644 frontend/src/hooks/use-rectification-live-activity.ts
 create mode 100644 frontend/src/lib/rectification-chat-accept-run.ts
 create mode 100644 frontend/src/lib/rectification-chat-choice-run.ts
 create mode 100644 frontend/src/lib/rectification-chat-message-actions.ts
 create mode 100644 frontend/src/lib/rectification-chat-messages.ts
 create mode 100644 frontend/src/lib/rectification-chat-question-repair.ts
 create mode 100644 frontend/src/lib/rectification-chat-snapshot.ts
 create mode 100644 frontend/src/lib/rectification-chat-turn-run.ts
 create mode 100644 frontend/src/lib/rectification-chat-view.ts
 create mode 100644 frontend/tests/rectification-chat-run-fixtures.ts
 create mode 100644 frontend/tests/rectification-chat-surface.ts
 create mode 100644 frontend/tests/rectification-growth-contract.test.ts

diff --git a/frontend/DESIGN.md b/frontend/DESIGN.md
index e175a2f9..06b43c33 100644
--- a/frontend/DESIGN.md
+++ b/frontend/DESIGN.md
@@ -798,7 +798,7 @@ Admin 的 antd `<Spin>` 是独立设计系统，不在此表。
 
 **「已对照 N 件」在手机上不在可见行里，桌面上目前仍在——这是一处未裁决的口径冲突。** 下面的禁列表写明这一项归交付卡、不上条，而它后来（cfb41daf）被加到了条上且没有改本文件。BUG-918 只把它在手机上移出可见行；桌面是否也撤掉需要产品裁决，见 `docs/BUG_HISTORY.md` BUG-918。
 
-**代表分钟上条是 D10（2026-09-16）的产品决定，推翻了「条上只有区间」的原设计。** 理由是窄屏：`.is-compact` 下右栏盘面整体变成默认关闭的 overlay，代表分钟此前只在 `.rectification-board__clock` 出现，于是用户最该一直看着的那个数字恰恰看不见。条上的取值必须与盘面标题行**同一次调用**——`workingRectificationTime(result)`，由 `rectification-agentic-chat.tsx` 算一次、两处共用，不允许第二条推导路径。已采用时写「已采用 HH:MM」，否则写「代表分钟 HH:MM」；**采用不是确认**，完整边界句仍只在交付 / 采用旁白里出现一次，条上不写、也不得暗示某一分钟已确认。
+**代表分钟上条是 D10（2026-09-16）的产品决定，推翻了「条上只有区间」的原设计。** 理由是窄屏：`.is-compact` 下右栏盘面整体变成默认关闭的 overlay，代表分钟此前只在 `.rectification-board__clock` 出现，于是用户最该一直看着的那个数字恰恰看不见。条上的取值必须与盘面标题行**同一次调用**——`workingRectificationTime(result)`，由 `rectification-chat-view.ts` 的 `deriveRectificationChatView` 算一次（容器 `rectification-agentic-chat.tsx` 每次渲染调用它一次；2026-09-26 代码拆分只搬位置）、两处共用，不允许第二条推导路径。已采用时写「已采用 HH:MM」，否则写「代表分钟 HH:MM」；**采用不是确认**，完整边界句仍只在交付 / 采用旁白里出现一次，条上不写、也不得暗示某一分钟已确认。
 
 **条上不得出现收窄进度（「已从 30 分钟收到 7 分钟」）。** 开场窗口确实在线上，但没有任何投影把这个对比作为字段给出，而 VOICE.md 第 2 条要求进度数字来自服务端。前端自己减还会算错：轴是**当前**窗口且会放宽（BUG-572），相减会把一次放宽报成进度。这句话继续由服务端拼进旁白。缺的字段见 `BLOCKED.md`。
 
diff --git a/frontend/src/components/rectification-agentic-chat.tsx b/frontend/src/components/rectification-agentic-chat.tsx
index 1e6d0ab1..d210ec7e 100644
--- a/frontend/src/components/rectification-agentic-chat.tsx
+++ b/frontend/src/components/rectification-agentic-chat.tsx
@@ -1,117 +1,37 @@
 "use client";
 
-import { startTransition, useCallback, useEffect, useId, useLayoutEffect, useRef, useState } from "react";
+import { useCallback, useEffect, useId, useRef, useState } from "react";
 import { useQueuedMessage } from "@/hooks/use-queued-message";
 import { appendQueuedText, queuedDraftSettleAction } from "@/lib/queued-draft";
 import { createPortal } from "react-dom";
-import { parseAgentReply } from "@/lib/agent-reply";
-import { nextActivityView, type AgentActivityView, type ChatMessage } from "@/lib/chat-message-view";
-import { createStreamFrameBuffer } from "@/lib/stream-frame-buffer";
-import {
-  completeActivityTrace,
-  completeActivityTraceStep,
-  emptyActivityTrace,
-  freezeLiveThink,
-  startActivityTraceStep,
-  type AgentActivityTraceItem,
-} from "@/lib/agent-activity-trace";
-import {
-  RECTIFICATION_ACTIVITY_PROGRESS_LABELS,
-  RECTIFICATION_ANALYZING_LIVE_LABEL,
-  RECTIFICATION_TOOL_DONE_LABELS,
-  RECTIFICATION_TOOL_PROGRESS_LABELS,
-  RECTIFICATION_TURN_PROGRESS_LABELS,
-  activityTraceFromReceipt,
-  rectificationCompletedTrail,
-  rectificationLiveProgressLabel,
-  rectificationToolActivityPhase,
-  rectificationTurnProgressPhase,
-} from "@/lib/rectification-activity-labels";
-import { isRectificationTurnProgressStage } from "@/lib/rectification-agentic/v9/turn-progress";
-import { withLiveStepLabel } from "@/lib/rectification-timeline-adapter";
-import {
-  createRectificationActivityReceiptState,
-  receiptFromRectificationActivityState,
-  reduceRectificationActivityReceipt,
-  type CompletedActivityReceiptView,
-} from "@/lib/rectification-activity-receipt";
-import {
-  canShowRectificationReadonlyRange,
-  canShowRectificationSelectionCards,
-  natalRecastMeaning,
-  parseRectificationCandidateResult,
-  workingRectificationHouseTable,
-  type RectificationCandidateResult,
-} from "@/lib/rectification-candidate-result";
+import type { ChatMessage } from "@/lib/chat-message-view";
+import { canShowRectificationSelectionCards } from "@/lib/rectification-candidate-result";
 import { RectificationRangeDelivery } from "@/components/rectification-range-delivery";
 import {
-  diffRectificationBoard,
-  RECTIFICATION_BOARD_SPLIT_MIN_PX,
-  workingRectificationTime,
-} from "@/lib/rectification-board-model";
-import {
-  rectificationAdoptingLabel,
   RECTIFICATION_EMPTY_ACTION_LABEL,
   RECTIFICATION_EMPTY_COPY,
-  RECTIFICATION_INSUFFICIENT_CREDITS_NOTICE,
-  RECTIFICATION_QUESTION_PREPARING_LABEL,
-  RECTIFICATION_QUESTION_RELOAD_LABEL,
-  RECTIFICATION_QUESTION_REPAIR_FAILED_COPY,
-  RECTIFICATION_QUESTION_REPAIR_LIMIT,
   RECTIFICATION_QUESTION_RETRY_INTERVAL_MS,
-  RECTIFICATION_QUESTION_RETRY_LIMIT,
-  RECTIFICATION_QUESTION_UNAVAILABLE_COPY,
-  RECTIFICATION_SNAPSHOT_RETRY_LABEL,
-  RECTIFICATION_CHOICE_SUBMIT_FAILED_COPY,
-  RECTIFICATION_SNAPSHOT_UNAVAILABLE_COPY,
   RECTIFICATION_COLLECT_WAITING_PLACEHOLDER,
-  RECTIFICATION_DELIVERED_COPY,
-  isAbortError,
-  rectificationConversationState,
-  rectificationInitialLiveLabel,
   recompareHistoricalResult,
-  rectificationQuestionGapState,
-  rectificationReadonlyRangeCopy,
   contrastProbesFromReceipt,
-  searchWindowFromSnapshot,
-  caseStageFromSnapshot,
-  interviewCollectWaiting,
-  interviewChoiceCardUnavailable,
-  persistedQuestionSurface,
-  interviewStopReasonFromSnapshot,
-  interviewSessionOutcomeFromSnapshot,
-  birthTimeSourceFromSnapshot,
   type RectificationCaseSnapshotPayload,
-  type RectificationSnapshotFailure,
 } from "@/lib/rectification-surface-state";
 import { RectificationTimeline } from "@/components/rectification-timeline";
-import {
-  buildRectificationTimeline,
-  type RectificationTimelineStage,
-} from "@/lib/rectification-timeline-scale";
-import {
-  isPublicRectificationActivity,
-  isPublicRectificationMethod,
-  isPublicRectificationTool,
-} from "@/lib/rectification-agentic/v9/public-receipt";
-import { userFacingRunFailure, isIncompleteRunBanner } from "@/lib/rectification-agentic/v9/run-diagnostic";
 import {
   CHOICE_ACTION,
   SKIP_PROBE_ACTION,
   STOP_ACTION,
-  isStructuredChoiceUserText,
-  shouldContinueAfterStructuredChoice,
   stableChoiceActionKey,
   type ChoiceOptionId,
 } from "@/lib/rectification-agentic/v9/choice-action";
-import { postAdoptVerifyDoneCopy } from "@/lib/rectification-agentic/user-copy";
-import { isRectificationCaseStatus, isResumableStatus, type RectificationCaseStatus } from "@/lib/rectification-agentic/v9/case-status";
-import { isPersistedFocusId, parseRectificationChoiceCard, type ChoiceKey, type RectificationChoiceCard as ChoiceCardModel } from "@/lib/rectification-agentic/v9/choice-card";
+import type { ChoiceKey } from "@/lib/rectification-agentic/v9/choice-card";
 import type { PublicLanguageModel } from "@/lib/public-models";
 import { useConversationScrollAnchor } from "@/hooks/use-conversation-scroll-anchor";
 import { useVisibilityAwarePoll } from "@/hooks/use-visibility-aware-poll";
+import { useRectificationCaseSnapshot } from "@/hooks/use-rectification-case-snapshot";
+import { useRectificationBoardLayout } from "@/hooks/use-rectification-board-layout";
+import { useRectificationLiveActivity } from "@/hooks/use-rectification-live-activity";
 import { ChatComposer } from "./chat-composer";
-import { ConsultationTimelineLiveRow } from "./consultation-run-timeline";
 import { JumpToLatestButton } from "./jump-to-latest-button";
 import { toggleChatMessageFeedback } from "./chat-message-actions";
 import {
@@ -121,107 +41,36 @@ import {
 } from "./rectification-message-entry";
 import { ModelSelector } from "./model-selector";
 import { RectificationBoard, RectificationBoardPeek } from "./rectification-board";
-import { RectificationChoiceCard } from "./rectification-choice-card";
+import {
+  RectificationQuestionGapNotices,
+  RectificationReadonlyRange,
+} from "./rectification-question-gap-notices";
 import {
   applyLiveCandidateOffer,
-  copyTextForMessage,
-  interviewQuestionBlocksAdoptOffer,
-  nextSelectionCardLock,
-  parseTurnQuestion,
-  questionIsAnswered,
-  resolveSelectionCardMessageKey,
-  turnQuestionFromCurrent,
   type SelectionCardLock,
 } from "@/lib/rectification-agentic/v9/turn-question";
 import { Button } from "@/components/ui/button";
+import { messagesFromTurns, type PersistedTurn } from "@/lib/rectification-chat-messages";
+import { runRectificationChatTurn } from "@/lib/rectification-chat-turn-run";
 import {
-  appendUnseenAssistantTurns,
-  applySnapshotTurnsToMessages,
-  mergeTurnQuestions,
-  placePersistedQuestion,
-} from "@/lib/rectification-snapshot-messages";
-
-type PersistedTurn = Readonly<{
-  id: string;
-  role: "user" | "assistant";
-  text: string | null;
-  status: string;
-  question?: unknown;
-  offer_result_id?: string | null;
-  receipt?: Readonly<{
-    status: string;
-    phases: readonly string[];
-    tool_activities?: readonly Readonly<{
-      tool: string;
-      status: string;
-      methods?: readonly string[];
-      started_at?: string | null;
-      elapsed_ms?: number | null;
-      detail?: Readonly<Record<string, unknown>> | null;
-    }>[];
-    tools: readonly string[];
-    methods?: readonly string[];
-    skill_name?: string;
-    skill_version?: string;
-  }> | null;
-}>;
+  runRectificationStructuredChoice,
+  type RectificationStructuredChoiceAction,
+  type RectificationStructuredChoiceOverride,
+} from "@/lib/rectification-chat-choice-run";
+import { runRectificationCandidateAccept } from "@/lib/rectification-chat-accept-run";
+import {
+  copyRectificationMessage,
+  regenerateRectificationMessage,
+} from "@/lib/rectification-chat-message-actions";
+import {
+  refetchRectificationQuestion,
+  repairRectificationQuestion,
+} from "@/lib/rectification-chat-question-repair";
+import { deriveRectificationChatView } from "@/lib/rectification-chat-view";
 
 /** Same ceiling as the main chat composer, so both surfaces count down the same way. */
 const RECTIFICATION_COMPOSER_MAX_LENGTH = 500;
 
-type CandidateResult = RectificationCandidateResult | null;
-type CurrentQuestionModel = Readonly<{
-  kind: "choice" | "collect_spoken";
-  prompt: string | null;
-  focus_id: string | null;
-  question_id: string | null;
-}>;
-
-function currentQuestionFromSnapshot(value: unknown): CurrentQuestionModel | null {
-  if (!value || typeof value !== "object" || Array.isArray(value)) return null;
-  const question = value as { kind?: unknown; prompt?: unknown; focus_id?: unknown; question_id?: unknown };
-  if (question.kind !== "choice" && question.kind !== "collect_spoken" && question.kind !== "reverse_verify") {
-    return null;
-  }
-  return {
-    kind: question.kind === "collect_spoken" ? "collect_spoken" : "choice",
-    prompt: typeof question.prompt === "string" && question.prompt.trim()
-      ? question.prompt.trim()
-      : null,
-    focus_id: typeof question.focus_id === "string" ? question.focus_id : null,
-    question_id: typeof question.question_id === "string" ? question.question_id : null,
-  };
-}
-
-function questionSourceFromSnapshot(value: unknown): "focus" | "unavailable" | null {
-  if (value === "unavailable") return "unavailable";
-  if (value === "focus") return "focus";
-  return null;
-}
-
-function RectificationReadonlyRange({
-  range,
-  sessionOutcome,
-  discriminatingEventProbes,
-  contrastProbes,
-}: Readonly<{
-  range: readonly [string, string];
-  sessionOutcome: string | null;
-  discriminatingEventProbes: unknown;
-  contrastProbes: unknown;
-}>) {
-  return (
-    <p className="rectification-readonly-range" role="status">
-      {rectificationReadonlyRangeCopy({
-        range,
-        sessionOutcome,
-        discriminatingEventProbes,
-        contrastProbes,
-      })}
-    </p>
-  );
-}
-
 type RectificationAgenticChatProps = Readonly<{
   caseId: string;
   sessionId: string;
@@ -249,76 +98,6 @@ type RectificationAgenticChatProps = Readonly<{
   headerSlot: HTMLElement | null;
 }>;
 
-function markQuestionAnswered(
-  current: RenderMessage[],
-  focusId: string,
-  selected: ChoiceKey | "stop" | "skip_probe" | "typed",
-): RenderMessage[] {
-  return current.map((message) => {
-    const question = message.question;
-    if (!question || question.focus_id !== focusId || questionIsAnswered(question)) return message;
-    return {
-      ...message,
-      question: {
-        ...question,
-        status: "resolved",
-        answer_option: selected === "typed" ? null : selected,
-      },
-    };
-  });
-}
-
-/**
- * BUG-1046: undo `markQuestionAnswered` when the answer never reached the
- * server, so the question is active again with no option picked. Only the mark
- * this action made is undone; a server-resolved question is left alone.
- */
-function withdrawAnswerMark(
-  current: RenderMessage[],
-  focusId: string,
-  selected: ChoiceKey | "stop" | "skip_probe" | "typed",
-): RenderMessage[] {
-  const marked = selected === "typed" ? null : selected;
-  return current.map((message) => {
-    const question = message.question;
-    if (!question || question.focus_id !== focusId) return message;
-    if (question.status !== "resolved" || question.answer_option !== marked) return message;
-    return { ...message, question: { ...question, status: "active", answer_option: null } };
-  });
-}
-
-function isSettledAssistantMessage(message: RenderMessage): boolean {
-  return message.role === "assistant" && message.state === "settled" && !message.failed;
-}
-
-function snapshotTurns(payload: { turns?: unknown } | null | undefined): readonly unknown[] {
-  return Array.isArray(payload?.turns) ? payload.turns : [];
-}
-
-function completedReceiptFromPersisted(receipt: PersistedTurn["receipt"]): CompletedActivityReceiptView {
-  if (!receipt) return { steps: [], methods: [] };
-  if (Array.isArray(receipt.tool_activities)) {
-    let state = createRectificationActivityReceiptState();
-    for (const activity of receipt.tool_activities) {
-      if (!isPublicRectificationTool(activity.tool)
-        || (activity.status !== "completed" && activity.status !== "failed")) continue;
-      state = reduceRectificationActivityReceipt(state, {
-        tool: activity.tool,
-        status: activity.status,
-        methods: activity.status === "completed" && Array.isArray(activity.methods)
-          ? activity.methods.filter(isPublicRectificationMethod)
-          : [],
-      });
-    }
-    return receiptFromRectificationActivityState(state);
-  }
-  return {
-    steps: [...new Set((receipt.tools ?? []).filter(isPublicRectificationTool))],
-    methods: [...new Set((receipt.methods ?? []).filter(isPublicRectificationMethod))],
-  };
-}
-
-
 export function toggleRectificationFeedback(
   current: "up" | "down" | undefined,
   requested: "up" | "down",
@@ -326,96 +105,6 @@ export function toggleRectificationFeedback(
   return toggleChatMessageFeedback(current, requested);
 }
 
-function hasActivityReceipt(receipt: CompletedActivityReceiptView): boolean {
-  return receipt.steps.length > 0 || receipt.methods.length > 0 || Boolean(receipt.failedTool);
-}
-
-function persistedTurnFailed(turn: PersistedTurn): boolean {
-  return turn.status === "failed"
-    || turn.status === "retryable"
-    || turn.receipt?.status === "failed"
-    || turn.receipt?.status === "degraded"
-    || turn.receipt?.status === "blocked";
-}
-
-function messagesFromTurns(initialTurns: readonly PersistedTurn[]): RenderMessage[] {
-  return initialTurns.flatMap((turn, index): RenderMessage[] => {
-    const key = `persisted-${turn.id}-${index}`;
-    if (turn.role === "assistant") {
-      const failed = persistedTurnFailed(turn);
-      const raw = failed ? "" : turn.text ?? "";
-      if (failed && !raw) return [];
-      if (isIncompleteRunBanner(raw)) return [];
-      const completedReceipt = completedReceiptFromPersisted(turn.receipt);
-      return [{
-        role: "assistant",
-        text: raw,
-        renderKey: key,
-        state: turn.status === "completed" || failed ? "settled" : "thinking",
-        completedReceipt,
-        activityTrace: activityTraceFromReceipt(completedReceipt),
-        failed,
-        turnId: turn.id,
-        question: parseTurnQuestion(turn.question) ?? undefined,
-        candidateOffer: typeof turn.offer_result_id === "string"
-          ? { resultId: turn.offer_result_id }
-          : undefined,
-      }];
-    }
-    if (isIncompleteRunBanner(turn.text ?? "")) return [];
-    if (isStructuredChoiceUserText(turn.text)) return [];
-    return [{
-      role: "user",
-      text: turn.text ?? "",
-      renderKey: key,
-      state: "settled",
-    }];
-  });
-}
-
-type CaseSnapshotState = Readonly<{
-  candidate: CandidateResult;
-  question: CurrentQuestionModel | null;
-  questionSource: "focus" | "unavailable" | null;
-  choice: ChoiceCardModel | null;
-  caseStatus: RectificationCaseStatus | null;
-  savedTime: string | null;
-  savedStatus: "accepted" | "confirmed" | null;
-  nextUserActionId: string | null;
-  searchWindow: readonly [string, string] | null;
-  stage: RectificationTimelineStage | null;
-  interviewStopReason: string | null;
-  interviewSessionOutcome: string | null;
-  birthTimeSource: ReturnType<typeof birthTimeSourceFromSnapshot>;
-}>;
-
-function nextUserActionIdFromSnapshot(payload: RectificationCaseSnapshotPayload | null): string | null {
-  const id = payload?.next_user_action?.id;
-  return typeof id === "string" && id.trim() ? id.trim() : null;
-}
-
-/** The snapshot that arrived with the reveal, as initial state; nothing is fetched on mount. */
-function caseSnapshotState(payload: RectificationCaseSnapshotPayload | null): CaseSnapshotState | null {
-  if (!payload) return null;
-  const confirmedTime = typeof payload.case?.confirmed_time === "string" ? payload.case.confirmed_time : null;
-  const acceptedTime = typeof payload.case?.accepted_time === "string" ? payload.case.accepted_time : null;
-  return {
-    candidate: parseRectificationCandidateResult(payload.latest_result),
-    question: currentQuestionFromSnapshot(payload.current_question),
-    questionSource: questionSourceFromSnapshot(payload.question_source),
-    choice: parseRectificationChoiceCard(payload.choice_card),
-    caseStatus: isRectificationCaseStatus(payload.case?.status) ? payload.case.status : null,
-    savedTime: confirmedTime ?? acceptedTime,
-    savedStatus: confirmedTime ? "confirmed" : acceptedTime ? "accepted" : null,
-    nextUserActionId: nextUserActionIdFromSnapshot(payload),
-    searchWindow: searchWindowFromSnapshot(payload.case?.candidate_range),
-    stage: caseStageFromSnapshot(payload.case?.stage),
-    interviewStopReason: interviewStopReasonFromSnapshot(payload),
-    interviewSessionOutcome: interviewSessionOutcomeFromSnapshot(payload),
-    birthTimeSource: birthTimeSourceFromSnapshot(payload),
-  };
-}
-
 export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
   const {
     caseId,
@@ -441,8 +130,41 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
     headerSlot,
   } = props;
 
-  const [resultNotice, setResultNotice] = useState(initialSnapshot?.case?.result_notice ?? null);
-  const [canRecompare, setCanRecompare] = useState(initialSnapshot?.case?.result_identity?.can_recompare === true);
+  // Case snapshot sync (candidate, current question, choice card, saved time,
+  // timeline window / stage, question recovery counters) lives in its own hook.
+  const {
+    resultNotice,
+    canRecompare,
+    savedTime,
+    setSavedTime,
+    savedStatus,
+    setSavedStatus,
+    candidateResult,
+    setCandidateResult,
+    choiceCard,
+    currentQuestion,
+    questionSource,
+    caseStatus,
+    searchWindow,
+    caseStage,
+    nextUserActionId,
+    setNextUserActionId,
+    interviewStopReason,
+    interviewSessionOutcome,
+    birthTimeSource,
+    caseSnapshotLoaded,
+    questionRetryAttempts,
+    setQuestionRetryAttempts,
+    questionRepairAttempts,
+    setQuestionRepairAttempts,
+    questionRepairing,
+    setQuestionRepairing,
+    snapshotFailure,
+    snapshotAbort,
+    currentQuestionRef,
+    applyCaseSnapshot,
+    loadCaseSnapshot,
+  } = useRectificationCaseSnapshot({ caseId, sessionId, initialSnapshot });
   const readonly = historyReadonly || Boolean(resultNotice);
   const conversationReadonly = historyReadonly || (Boolean(resultNotice) && !canRecompare);
   const [messages, setMessages] = useState<RenderMessage[]>(() => messagesFromTurns(initialTurns));
@@ -451,24 +173,6 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
   const lastRunOutcome = useRef<"succeeded" | "stopped" | "failed" | "readonly" | null>(null);
   const [busy, setBusy] = useState(false);
   const [error, setError] = useState("");
-  const [savedTime, setSavedTime] = useState<string | null>(() => caseSnapshotState(initialSnapshot)?.savedTime ?? null);
-  const [savedStatus, setSavedStatus] = useState<"accepted" | "confirmed" | null>(() => caseSnapshotState(initialSnapshot)?.savedStatus ?? null);
-  const [candidateResult, setCandidateResult] = useState<CandidateResult>(() => caseSnapshotState(initialSnapshot)?.candidate ?? null);
-  const [choiceCard, setChoiceCard] = useState<ChoiceCardModel | null>(() => caseSnapshotState(initialSnapshot)?.choice ?? null);
-  const [currentQuestion, setCurrentQuestion] = useState<CurrentQuestionModel | null>(() => caseSnapshotState(initialSnapshot)?.question ?? null);
-  const [questionSource, setQuestionSource] = useState<"focus" | "unavailable" | null>(() => caseSnapshotState(initialSnapshot)?.questionSource ?? null);
-  const [caseStatus, setCaseStatus] = useState<RectificationCaseStatus | null>(() => caseSnapshotState(initialSnapshot)?.caseStatus ?? null);
-  const [searchWindow, setSearchWindow] = useState<readonly [string, string] | null>(() => caseSnapshotState(initialSnapshot)?.searchWindow ?? null);
-  const [caseStage, setCaseStage] = useState<RectificationTimelineStage | null>(() => caseSnapshotState(initialSnapshot)?.stage ?? null);
-  const [nextUserActionId, setNextUserActionId] = useState<string | null>(() => caseSnapshotState(initialSnapshot)?.nextUserActionId ?? null);
-  const [interviewStopReason, setInterviewStopReason] = useState<string | null>(() => caseSnapshotState(initialSnapshot)?.interviewStopReason ?? null);
-  const [interviewSessionOutcome, setInterviewSessionOutcome] = useState<string | null>(() => caseSnapshotState(initialSnapshot)?.interviewSessionOutcome ?? null);
-  const [birthTimeSource, setBirthTimeSource] = useState(() => caseSnapshotState(initialSnapshot)?.birthTimeSource ?? birthTimeSourceFromSnapshot(initialSnapshot));
-  const [caseSnapshotLoaded, setCaseSnapshotLoaded] = useState(initialSnapshot !== null);
-  const [questionRetryAttempts, setQuestionRetryAttempts] = useState(0);
-  const [questionRepairAttempts, setQuestionRepairAttempts] = useState(0);
-  const [questionRepairing, setQuestionRepairing] = useState(false);
-  const [snapshotFailure, setSnapshotFailure] = useState<RectificationSnapshotFailure | null>(null);
   const [openingRequested, setOpeningRequested] = useState(false);
   const [acceptingCandidateId, setAcceptingCandidateId] = useState<string | null>(null);
   const [feedback, setFeedback] = useState<Record<string, "up" | "down" | undefined>>({});
@@ -487,48 +191,22 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
   const composer = useRef<HTMLTextAreaElement>(null);
   const keyCounter = useRef(0);
   const openingStarted = useRef(false);
-  const previousBoardResult = useRef<CandidateResult>(null);
   const runAbort = useRef<AbortController | null>(null);
-  const snapshotAbort = useRef<AbortController | null>(null);
   const choiceActionIds = useRef(new Map<string, string>());
-  const currentQuestionRef = useRef(currentQuestion);
-  const runStartedAtRef = useRef(0);
-  const stepStartedAtRef = useRef(0);
-  const liveToolRef = useRef<string | null>(null);
-  const liveBaseLabelRef = useRef("正在处理…");
   const [selectionOfferLock, setSelectionOfferLock] = useState<SelectionCardLock | null>(null);
-  const [compactBoard, setCompactBoard] = useState(false);
-  const [boardOpen, setBoardOpen] = useState(false);
-  const [boardDiff, setBoardDiff] = useState(() => diffRectificationBoard(null, null));
-  const boardId = useId();
-  const boardTitleId = useId();
   const composerRemainingId = useId();
   // Same pin-the-turn-head hook as the consultation surface (BUG-930).
   const conversationAnchor = useConversationScrollAnchor(conversation, true, caseId);
-
-  useLayoutEffect(() => {
-    currentQuestionRef.current = currentQuestion;
-  }, [currentQuestion]);
-
-  useLayoutEffect(() => {
-    const query = window.matchMedia(`(max-width: ${RECTIFICATION_BOARD_SPLIT_MIN_PX - 1}px)`);
-    const update = () => {
-      const nextCompact = query.matches;
-      setCompactBoard(nextCompact);
-      if (!nextCompact) setBoardOpen(false);
-    };
-    update();
-    query.addEventListener("change", update);
-    return () => query.removeEventListener("change", update);
-  }, []);
-
-  useEffect(() => {
-    setBoardDiff(diffRectificationBoard(previousBoardResult.current, candidateResult));
-    previousBoardResult.current = candidateResult;
-  }, [candidateResult]);
-
-  const closeBoard = useCallback(() => setBoardOpen(false), []);
-  const toggleBoard = useCallback(() => setBoardOpen((current) => !current), []);
+  const {
+    compactBoard,
+    boardOpen,
+    boardDiff,
+    boardId,
+    boardTitleId,
+    closeBoard,
+    toggleBoard,
+  } = useRectificationBoardLayout(candidateResult);
+  const { beginLiveRun, rememberLiveActivity } = useRectificationLiveActivity({ busy, setMessages });
 
   const stopRun = useCallback(() => {
     runAbort.current?.abort();
@@ -542,46 +220,6 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
     onPendingChange?.(value);
   }, [onPendingChange]);
 
-  const beginLiveRun = useCallback((baseLabel: string) => {
-    const now = Date.now();
-    runStartedAtRef.current = now;
-    stepStartedAtRef.current = now;
-    liveToolRef.current = null;
-    liveBaseLabelRef.current = baseLabel;
-  }, []);
-
-  const rememberLiveActivity = useCallback((baseLabel: string, tool: string | null = liveToolRef.current) => {
-    if (liveBaseLabelRef.current !== baseLabel) {
-      liveBaseLabelRef.current = baseLabel;
-      stepStartedAtRef.current = Date.now();
-    }
-    liveToolRef.current = tool;
-    return rectificationLiveProgressLabel({
-      tool,
-      baseLabel,
-      stepStartedAt: stepStartedAtRef.current,
-      runStartedAt: runStartedAtRef.current,
-    });
-  }, []);
-
-  useEffect(() => {
-    if (!busy) return;
-    const id = window.setInterval(() => {
-      const label = rectificationLiveProgressLabel({
-        tool: liveToolRef.current,
-        baseLabel: liveBaseLabelRef.current,
-        stepStartedAt: stepStartedAtRef.current,
-        runStartedAt: runStartedAtRef.current,
-      });
-      setMessages((current) => current.map((message) => {
-        if (message.state !== "thinking" && message.state !== "streaming") return message;
-        if (!message.activity || message.activity.label === label) return message;
-        return { ...message, activity: { ...message.activity, label } };
-      }));
-    }, 4000);
-    return () => window.clearInterval(id);
-  }, [busy]);
-
   useEffect(() => {
     if (!candidateResult?.resultId) return;
     const canOffer = canShowRectificationSelectionCards(candidateResult);
@@ -597,109 +235,6 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
     });
   }, [candidateResult]);
 
-  // Candidate snapshot comes from the persisted Candidate Snapshot API, never
-  // from parsing agent text or hidden sentinels.
-  const applyCaseSnapshot = useCallback((payload: RectificationCaseSnapshotPayload | {
-    latest_result?: unknown;
-    current_question?: unknown;
-    choice_card?: unknown;
-    step_state?: unknown;
-    turns?: unknown;
-    question_source?: unknown;
-    next_user_action?: { id?: unknown };
-    interview?: { stop_reason?: unknown; session_outcome?: unknown };
-    case?: {
-      status?: unknown;
-      accepted_time?: unknown;
-      confirmed_time?: unknown;
-      candidate_range?: unknown;
-      stage?: unknown;
-    };
-  } | null) => {
-    if (!payload) return;
-    const snapshot = payload as RectificationCaseSnapshotPayload;
-    setResultNotice(snapshot.case?.result_notice ?? null);
-    setCanRecompare(snapshot.case?.result_identity?.can_recompare === true);
-    const nextCandidate = parseRectificationCandidateResult(payload.latest_result);
-    const nextQuestion = currentQuestionFromSnapshot(payload.current_question);
-    const nextChoice = parseRectificationChoiceCard(payload.choice_card);
-    const nextCaseStatus = isRectificationCaseStatus(payload.case?.status)
-      ? payload.case.status
-      : null;
-    const acceptedTime = typeof payload.case?.accepted_time === "string" ? payload.case.accepted_time : null;
-    const confirmedTime = typeof payload.case?.confirmed_time === "string" ? payload.case.confirmed_time : null;
-    const nextActionId = typeof payload.next_user_action?.id === "string"
-      ? payload.next_user_action.id.trim()
-      : "";
-    // Only overwrite when the payload actually carries them: a snapshot without
-    // a window should leave the timeline showing the last known one rather than
-    // dropping to the skeleton mid-session.
-    const nextWindow = searchWindowFromSnapshot(payload.case?.candidate_range);
-    if (nextWindow) setSearchWindow(nextWindow);
-    const nextStage = caseStageFromSnapshot(payload.case?.stage);
-    if (nextStage) setCaseStage(nextStage);
-    setCandidateResult(nextCandidate);
-    setCurrentQuestion(nextQuestion);
-    setQuestionSource(questionSourceFromSnapshot(payload.question_source));
-    setChoiceCard(nextChoice);
-    setCaseStatus(nextCaseStatus);
-    setNextUserActionId(nextActionId || null);
-    setInterviewStopReason(interviewStopReasonFromSnapshot(snapshot));
-    setInterviewSessionOutcome(interviewSessionOutcomeFromSnapshot(snapshot));
-    setBirthTimeSource(birthTimeSourceFromSnapshot(snapshot));
-    setCaseSnapshotLoaded(true);
-    if (nextQuestion || nextChoice || acceptedTime || confirmedTime) {
-      setQuestionRepairAttempts(0);
-    }
-    if (confirmedTime) {
-      setSavedTime(confirmedTime);
-      setSavedStatus("confirmed");
-    } else if (acceptedTime) {
-      setSavedTime(acceptedTime);
-      setSavedStatus("accepted");
-    }
-  }, []);
-
-  const loadCaseSnapshot = useCallback(async (
-    mergeMessages?: (turns: readonly unknown[]) => void,
-  ): Promise<{
-    question: CurrentQuestionModel | null;
-    turns: readonly unknown[];
-  } | null | undefined> => {
-    snapshotAbort.current?.abort();
-    const controller = new AbortController();
-    snapshotAbort.current = controller;
-    try {
-      const response = await fetch(
-        `/api/rectification/cases/${encodeURIComponent(caseId)}?sessionId=${encodeURIComponent(sessionId)}`,
-        { cache: "no-store", signal: controller.signal },
-      );
-      if (controller.signal.aborted) return undefined;
-      if (!response.ok) {
-        setSnapshotFailure({ status: response.status });
-        return undefined;
-      }
-      const payload = await response.json().catch(() => null);
-      if (controller.signal.aborted) return undefined;
-      const turns = snapshotTurns(payload);
-      startTransition(() => {
-        setSnapshotFailure(null);
-        applyCaseSnapshot(payload);
-        mergeMessages?.(turns);
-      });
-      return {
-        question: currentQuestionFromSnapshot(payload?.current_question),
-        turns,
-      };
-    } catch (error) {
-      if (isAbortError(error) || controller.signal.aborted) return undefined;
-      setSnapshotFailure({ status: "network" });
-      return undefined;
-    } finally {
-      if (snapshotAbort.current === controller) snapshotAbort.current = null;
-    }
-  }, [applyCaseSnapshot, caseId, sessionId]);
-
   // Turns that arrive after mount (the parent refreshes the Case after each
   // completed turn) only ever fill an empty transcript; a live or finished
   // conversation is never overwritten or remounted. Adjusted during render
@@ -718,398 +253,37 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
   }, []);
 
   /**
-   * Run one agent turn. A `continuation` reuses the live row an earlier step
-   * (a tapped choice, an adopted candidate) already put at the end of the
-   * transcript, so the reader sees one uninterrupted working row from the tap
-   * to the next question instead of a gap and a re-appended row. The caller
-   * of a continuation already holds `busy`.
+   * Run one agent turn (runRectificationChatTurn). A `continuation` reuses the
+   * live row an earlier step already put at the end of the transcript; the
+   * caller of a continuation already holds `busy`.
    */
   const send = useCallback(async (
     action: "opening" | "message" | "read_only",
     messageText: string,
     continuation?: Readonly<{ reuseAssistantRenderKey: string; label: string }>,
-  ) => {
-    const trimmed = action === "message" ? messageText.trim() : "";
-    if ((action === "message" && !trimmed) || conversationReadonly) return;
-    if (!continuation && busy) return;
-    setError("");
-    setPending(true);
-    const initialLabel = rectificationInitialLiveLabel(action, continuation?.label);
-    beginLiveRun(initialLabel);
-
-    keyCounter.current += 1;
-    const requestId = globalThis.crypto.randomUUID();
-    const turnKey = keyCounter.current;
-    const userRenderKey = `v9-user-${turnKey}`;
-    const assistantRenderKey = continuation?.reuseAssistantRenderKey ?? `v9-assistant-${turnKey}`;
-
-    const pendingFocusId = currentQuestionRef.current?.focus_id;
-    const liveRow: RenderMessage = {
-      role: "assistant",
-      text: "",
-      renderKey: assistantRenderKey,
-      state: "thinking",
-      activityTrace: emptyActivityTrace(),
-      activity: { phase: "evidence-validation", label: initialLabel, startedAt: Date.now() },
-    };
-    setMessages((current) => (continuation
-      ? current.map((message) => (message.renderKey === assistantRenderKey ? { ...liveRow, activity: message.activity ?? liveRow.activity } : message))
-      : [
-        ...(action === "message" && pendingFocusId
-          ? markQuestionAnswered(current, pendingFocusId, "typed")
-          : current),
-        ...(action === "message"
-          ? [{ role: "user", text: trimmed, renderKey: userRenderKey, state: "settled" } satisfies RenderMessage]
-          : []),
-        liveRow,
-      ]));
-    if (!continuation) conversationAnchor.pinLatestTurn();
-    // The typed answer never reached the server: the question it marked is
-    // still the pending one (BUG-1046, same as a failed tap).
-    const withdrawTypedMark = (current: RenderMessage[]) => (
-      !continuation && action === "message" && pendingFocusId
-        ? withdrawAnswerMark(current, pendingFocusId, "typed")
-        : current
-    );
-    let raw = "";
-    let runOutcome: "succeeded" | "stopped" | "failed" = "failed";
-    let activityTrace: readonly AgentActivityTraceItem[] = emptyActivityTrace();
-    let activityReceiptState = createRectificationActivityReceiptState();
-    let completedReceipt = receiptFromRectificationActivityState(activityReceiptState);
-    let completedTurnId: string | undefined;
-    let currentActivity: AgentActivityView | undefined = {
-      phase: "evidence-validation",
-      label: initialLabel,
-      startedAt: Date.now(),
-    };
-    // Every stream event lands in `frames`; it commits at most once per animation
-    // frame and releases text at a steady pace. The loop below never calls
-    // setMessages for a live turn directly except on `attempt.reset`.
-    const frames = createStreamFrameBuffer<null>({
-      initialMeta: null,
-      flush: (frame) => {
-        const text = frame.answer;
-        setMessages((current) => current.map((message) => message.renderKey === assistantRenderKey
-          ? {
-            ...message,
-            text,
-            activityTrace,
-            completedReceipt,
-            state: text.trim() ? "streaming" : "thinking",
-            activity: currentActivity,
-          }
-          : message));
-      },
-    });
-    const abortController = new AbortController();
-    runAbort.current = abortController;
-    try {
-      const response = await fetch("/api/rectification/agent", {
-        method: "POST",
-        headers: { "content-type": "application/json" },
-        signal: abortController.signal,
-        body: JSON.stringify({
-          caseId,
-          sessionId,
-          requestId,
-          action,
-          modelId: selectedModelId,
-          ...(action === "message" ? { message: trimmed } : {}),
-          origin: action === "read_only" ? "choice_click" : "typed",
-          clientActionId: requestId,
-        }),
-      });
-      // A turn the server turned down: the old non-2xx response, or the same
-      // facts as a `turn.rejected` event once the stream is already open
-      // (BUG-1047). Either way the live row goes and the typed mark returns.
-      const rejectTurn = (
-        response: { status: number },
-        payload: { code?: unknown; message?: unknown; error?: unknown } | null,
-      ) => {
-        const message = (typeof payload?.message === "string" && payload.message)
-          || (typeof payload?.error === "string" && payload.error)
-          || `请求失败（${response.status}）`;
-        setMessages((current) => withdrawTypedMark(
-          current.filter((message) => message.renderKey !== assistantRenderKey),
-        ));
-        if (payload?.code === "profile_incomplete") {
-          onProfileIncomplete?.();
-          return;
-        }
-        if (response.status === 402) {
-          // Keep the conversation on this page; the settings pane covers billing.
-          setError(RECTIFICATION_INSUFFICIENT_CREDITS_NOTICE);
-          onOpenBilling?.({ source: "rectification" });
-          return;
-        }
-        if (response.status === 401) setError("请先登录。");
-        else setError(message);
-      };
-      if (!response.ok) {
-        const payload = await response.json().catch(() => null);
-        rejectTurn(response, payload);
-        return;
-      }
-      if (!response.body) {
-        setMessages((current) => withdrawTypedMark(
-          current.filter((message) => message.renderKey !== assistantRenderKey),
-        ));
-        setError("服务暂时不可用，请稍后再试。");
-        return;
-      }
-
-      const reader = response.body.getReader();
-      const decoder = new TextDecoder();
-      let buffer = "";
-      let completed = false;
-      let streamFailed = false;
-      let runFailedMessage = "";
-      let rejected: { status: number; payload: { code?: unknown; message?: unknown } } | null = null;
-      // Stage line of a typed answer (BUG-1047 D3); null until the first
-      // `turn.progress`. It replaces the generic tool / "正在分析…" labels.
-      let stageLabel: string | null = null;
-      while (!rejected) {
-        const { done, value } = await reader.read();
-        if (done) break;
-        buffer += decoder.decode(value, { stream: true });
-        const lines = buffer.split("\n");
-        buffer = lines.pop() ?? "";
-        for (const line of lines) {
-          if (!line.trim()) continue;
-          let event: {
-            type?: unknown;
-            status?: unknown;
-            text?: unknown;
-            replace?: unknown;
-            message?: unknown;
-            tool?: unknown;
-            methods?: unknown;
-            turnId?: unknown;
-            code?: unknown;
-            activity?: unknown;
-            stage?: unknown;
-            httpStatus?: unknown;
-          };
-          try {
-            event = JSON.parse(line) as typeof event;
-          } catch {
-            continue;
-          }
-          if (typeof event.type !== "string") continue;
-          if (event.type === "turn.rejected" && typeof event.httpStatus === "number") {
-            rejected = { status: event.httpStatus, payload: { code: event.code, message: event.message } };
-            break;
-          }
-          if (event.type === "turn.progress" && isRectificationTurnProgressStage(event.stage)) {
-            stageLabel = RECTIFICATION_TURN_PROGRESS_LABELS[event.stage];
-            activityTrace = withLiveStepLabel(activityTrace, stageLabel);
-            currentActivity = nextActivityView(currentActivity, {
-              phase: rectificationTurnProgressPhase(event.stage),
-              label: rememberLiveActivity(stageLabel, null),
-            });
-            frames.touch();
-          } else if (event.type === "answer.delta" && typeof event.text === "string") {
-            raw = event.replace === true ? event.text : raw + event.text;
-            activityTrace = freezeLiveThink(activityTrace);
-            currentActivity = nextActivityView(currentActivity, {
-              phase: "answer-composition",
-              label: rememberLiveActivity("正在组织回答…"),
-            });
-            frames.setAnswer(raw);
-          } else if (event.type === "activity.changed" && isPublicRectificationActivity(event.activity)) {
-            const activity = event.activity;
-            currentActivity = nextActivityView(currentActivity, {
-              phase: "evidence-validation",
-              label: rememberLiveActivity(stageLabel ?? RECTIFICATION_ACTIVITY_PROGRESS_LABELS[activity]),
-            });
-            frames.touch();
-          } else if (event.type === "attempt.reset") {
-            raw = "";
-            activityTrace = emptyActivityTrace();
-            activityReceiptState = createRectificationActivityReceiptState();
-            completedReceipt = receiptFromRectificationActivityState(activityReceiptState);
-            completedTurnId = undefined;
-            if (stageLabel) stageLabel = RECTIFICATION_TURN_PROGRESS_LABELS.received;
-            currentActivity = nextActivityView(undefined, {
-              phase: "evidence-validation",
-              label: rememberLiveActivity(stageLabel ?? "正在处理…", null),
-            });
-            frames.reset();
-            setMessages((current) => current.map((message) => message.renderKey === assistantRenderKey
-              ? {
-                ...message,
-                text: "",
-                thinkingText: undefined,
-                activityTrace,
-                state: "thinking",
-                completedReceipt: undefined,
-                failed: false,
-                turnId: undefined,
-                activity: currentActivity,
-              }
-              : message));
-          } else if (event.type === "run.failed") {
-            streamFailed = true;
-            runFailedMessage = typeof event.message === "string" && event.message.trim()
-              ? event.message
-              : userFacingRunFailure(typeof event.code === "string" ? event.code : null);
-          } else if (event.type === "error") {
-            streamFailed = true;
-            setError(typeof event.message === "string" ? event.message : "生时校正暂时不可用，请稍后再试。");
-          } else if (event.type === "run.completed") {
-            completed = true;
-            if (typeof event.turnId === "string") completedTurnId = event.turnId;
-          } else if (event.type === "tool.activity") {
-            const tool = isPublicRectificationTool(event.tool) ? event.tool : null;
-            if (!tool) continue;
-            if (event.status === "started") {
-              activityTrace = startActivityTraceStep(
-                activityTrace,
-                tool,
-                stageLabel ?? RECTIFICATION_TOOL_PROGRESS_LABELS[tool],
-              );
-              currentActivity = nextActivityView(currentActivity, {
-                phase: rectificationToolActivityPhase(tool),
-                label: rememberLiveActivity(stageLabel ?? RECTIFICATION_TOOL_PROGRESS_LABELS[tool], tool),
-                completedTrail: rectificationCompletedTrail(activityReceiptState.completedSteps),
-              });
-              frames.touch();
-              continue;
-            }
-            if (event.status !== "completed" && event.status !== "failed") continue;
-            activityTrace = completeActivityTraceStep(
-              activityTrace,
-              tool,
-              RECTIFICATION_TOOL_DONE_LABELS[tool],
-            );
-            activityReceiptState = reduceRectificationActivityReceipt(activityReceiptState, {
-              tool,
-              status: event.status,
-              methods: event.status === "completed" && Array.isArray(event.methods)
-                ? event.methods.filter(isPublicRectificationMethod)
-                : [],
-            });
-            completedReceipt = receiptFromRectificationActivityState(activityReceiptState);
-            currentActivity = nextActivityView(currentActivity, {
-              phase: "evidence-validation",
-              label: stageLabel
-                ? rememberLiveActivity(stageLabel, null)
-                : rememberLiveActivity(RECTIFICATION_ANALYZING_LIVE_LABEL, null),
-              completedTrail: rectificationCompletedTrail(activityReceiptState.completedSteps),
-            });
-            frames.touch();
-          }
-        }
-      }
-      frames.settle();
-      if (rejected) {
-        await reader.cancel().catch(() => undefined);
-        rejectTurn({ status: rejected.status }, rejected.payload);
-        return;
-      }
-
-      const parsed = completed && !streamFailed ? parseAgentReply(raw) : { text: "", title: undefined };
-      const succeeded = completed && !streamFailed && Boolean(parsed.text);
-      setMessages((current) => current.flatMap((message): RenderMessage[] => {
-        if (message.renderKey !== assistantRenderKey) return [message];
-        if (succeeded) {
-          return [{
-            ...message,
-            text: parsed.text,
-            activityTrace: completeActivityTrace(activityTrace),
-            state: "settled",
-            completedReceipt,
-            failed: false,
-            turnId: completedTurnId,
-            activity: undefined,
-          }];
-        }
-        if (streamFailed || hasActivityReceipt(completedReceipt) || raw.trim()) {
-          return [{
-            ...message,
-            text: raw,
-            activityTrace: completeActivityTrace(activityTrace),
-            state: "settled",
-            completedReceipt,
-            failed: true,
-            activity: undefined,
-          }];
-        }
-        return [];
-      }));
-      if (!succeeded && raw.trim()) {
-        setError((current) => current || "回答未完成，已保留现有内容；本次不会扣点。");
-      } else if (!succeeded && runFailedMessage) {
-        setError((current) => current || runFailedMessage);
-      } else if (!succeeded && completedReceipt.failedTool) {
-        setError((current) => current || userFacingRunFailure("run_failed"));
-      }
-      if (succeeded) {
-        runOutcome = "succeeded";
-        await loadCaseSnapshot((turns) => {
-          if (turns.length) {
-            // D4 (BUG-1046): a turn the server wrote alongside this one (the
-            // one carrying the next question) joins the transcript too.
-            setMessages((current) => applySnapshotTurnsToMessages(
-              current,
-              turns,
-              (incoming) => messagesFromTurns(incoming as readonly PersistedTurn[]),
-            ));
-          }
-        });
-        onMessagesChange?.([
-          ...(action === "message" ? [{ role: "user" as const, text: trimmed }] : []),
-          { role: "assistant", text: parsed.text },
-        ]);
-        onCompleted?.();
-      } else {
-        await loadCaseSnapshot((turns) => {
-          if (turns.length) {
-            setMessages((current) => mergeTurnQuestions(current, turns));
-          }
-        });
-      }
-    } catch (caught) {
-      frames.settle();
-      const aborted = isAbortError(caught);
-      if (aborted) {
-        runOutcome = "stopped";
-        setMessages((current) => current.map((message) => {
-          if (message.renderKey !== assistantRenderKey) return message;
-          return {
-            ...message,
-            text: raw,
-            activityTrace: completeActivityTrace(activityTrace),
-            state: "settled" as const,
-            completedReceipt,
-            failed: false,
-            stopped: true,
-            turnId: completedTurnId,
-            activity: undefined,
-          };
-        }));
-        return;
-      }
-      setError("生时校正暂时不可用，请稍后再试。");
-      setMessages((current) => withdrawTypedMark(current).flatMap((message): RenderMessage[] => {
-        if (message.renderKey !== assistantRenderKey) return [message];
-        return hasActivityReceipt(completedReceipt)
-          ? [{
-            ...message,
-            text: "",
-            state: "settled",
-            completedReceipt,
-            failed: true,
-          }]
-          : [];
-      }));
-    } finally {
-      frames.dispose();
-      if (runAbort.current === abortController) runAbort.current = null;
-      lastRunOutcome.current = readonly ? "readonly" : runOutcome;
-      setPending(false);
-    }
-  }, [beginLiveRun, busy, caseId, loadCaseSnapshot, onCompleted, onMessagesChange, onOpenBilling, onProfileIncomplete, readonly, conversationReadonly, rememberLiveActivity, selectedModelId, sessionId, setPending]);
+  ) => runRectificationChatTurn({
+    caseId,
+    sessionId,
+    selectedModelId,
+    busy,
+    readonly,
+    conversationReadonly,
+    keyCounter,
+    currentQuestionRef,
+    runAbort,
+    lastRunOutcome,
+    conversationAnchor,
+    setError,
+    setMessages,
+    setPending,
+    beginLiveRun,
+    rememberLiveActivity,
+    loadCaseSnapshot,
+    onCompleted,
+    onMessagesChange,
+    onOpenBilling,
+    onProfileIncomplete,
+  }, action, messageText, continuation), [beginLiveRun, busy, caseId, loadCaseSnapshot, onCompleted, onMessagesChange, onOpenBilling, onProfileIncomplete, readonly, conversationReadonly, rememberLiveActivity, selectedModelId, sessionId, setPending]);
 
   useEffect(() => {
     if (busy) return;
@@ -1135,186 +309,33 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
   }, []);
 
   const submitStructuredChoice = useCallback(async (
-    action: typeof CHOICE_ACTION | typeof STOP_ACTION | typeof SKIP_PROBE_ACTION,
+    action: RectificationStructuredChoiceAction,
     optionId: ChoiceKey | "stop" | "skip_probe",
-    override?: Readonly<{
-      focusId?: string;
-      questionId?: string | null;
-      probeId?: string | null;
-      caseRevision?: number | null;
-    }>,
-  ) => {
-    const focusId = override?.focusId ?? choiceCard?.focus_id ?? (
-      action === STOP_ACTION && currentQuestion?.kind === "collect_spoken"
-        ? currentQuestion.focus_id
-        : null
-    );
-    if (busy || readonly) return;
-    if (action !== STOP_ACTION && (!focusId || (!override && !choiceCard))) return;
-    if (focusId && !isPersistedFocusId(focusId)) {
-      setError("当前选择题已失效，请等待下一问。");
-      return;
-    }
-    const questionId = override?.questionId ?? choiceCard?.question_id ?? currentQuestion?.question_id ?? null;
-    const probeId = override?.probeId ?? choiceCard?.probe_id;
-    const expectedRevision = override?.caseRevision ?? choiceCard?.case_revision ?? 0;
-    const actionId = actionIdForChoice(focusId ?? caseId, optionId);
-    setError("");
-    keyCounter.current += 1;
-    const turnKey = keyCounter.current;
-    const assistantRenderKey = `v9-choice-assistant-${turnKey}`;
-    const recordingLabel = RECTIFICATION_ACTIVITY_PROGRESS_LABELS.recording_answer;
-    beginLiveRun(recordingLabel);
-    setMessages((current) => [
-      ...markQuestionAnswered(current, focusId ?? "", optionId),
-      {
-        role: "assistant",
-        text: "",
-        renderKey: assistantRenderKey,
-        state: "thinking",
-        activityTrace: emptyActivityTrace(),
-        activity: {
-          phase: "evidence-validation",
-          label: recordingLabel,
-          startedAt: Date.now(),
-        },
-      },
-    ]);
-    conversationAnchor.pinLatestTurn();
-    setPending(true);
-    // BUG-1046 (D2): a tap that did not land takes back its local answered
-    // mark and placeholder; the card key changes (answer_option → nonce), so
-    // the card remounts clean and one tappable card is left.
-    const rollBackFailedChoice = () => {
-      setMessages((current) => withdrawAnswerMark(
-        current.filter((message) => message.renderKey !== assistantRenderKey),
-        focusId ?? "",
-        optionId,
-      ));
-      setChoiceNonce((current) => current + 1);
-    };
-    // The server may have moved on (stale_question, a dropped response after
-    // it applied): re-read the Case so the card reflects what it holds.
-    const reloadAfterFailedChoice = () => loadCaseSnapshot((turns) => {
-      setMessages((current) => applySnapshotTurnsToMessages(
-        current,
-        turns,
-        (incoming) => messagesFromTurns(incoming as readonly PersistedTurn[]),
-      ));
-    });
-    const abortController = new AbortController();
-    runAbort.current = abortController;
-    try {
-      const response = await fetch("/api/rectification/agent", {
-        method: "POST",
-        headers: { "content-type": "application/json" },
-        signal: abortController.signal,
-        body: JSON.stringify({
-          caseId,
-          sessionId,
-          requestId: actionId,
-          action,
-          actionId,
-          ...(focusId ? { focusId } : {}),
-          ...(questionId ? { questionId } : {}),
-          probeId: probeId ?? null,
-          optionId: optionId === "stop" ? undefined : optionId,
-          expectedRevision,
-          origin: "choice_click",
-          clientActionId: actionId,
-        }),
-      });
-      const payload = await response.json().catch(() => null);
-      if (!response.ok) {
-        rollBackFailedChoice();
-        if (payload?.code === "profile_incomplete") {
-          onProfileIncomplete?.();
-          return;
-        }
-        setError(RECTIFICATION_CHOICE_SUBMIT_FAILED_COPY);
-        await reloadAfterFailedChoice();
-        return;
-      }
-      const willContinue = shouldContinueAfterStructuredChoice(payload?.nextAction, payload);
-      const payloadNextActionId = typeof payload?.next_user_action?.id === "string"
-        ? payload.next_user_action.id.trim()
-        : "";
-      if (payloadNextActionId) setNextUserActionId(payloadNextActionId);
-      onCompleted?.();
-      await loadCaseSnapshot((turns) => {
-        if (willContinue) {
-          // D4 (BUG-1046, the same gap BUG-685 closed for the tie-break entry): a turn
-          // the server wrote while applying the tap joins the transcript,
-          // above the row the follow-up run continues on.
-          setMessages((current) => mergeTurnQuestions(
-            appendUnseenAssistantTurns(
-              current,
-              messagesFromTurns(turns as readonly PersistedTurn[]),
-              { beforeRenderKey: assistantRenderKey },
-            ),
-            turns,
-          ));
-          return;
-        }
-        const narration = typeof payload?.narration === "string" && payload.narration.trim()
-          ? payload.narration.trim()
-          : "已记录你的选择。";
-        setMessages((current) => {
-          const withoutPlaceholder = current.filter((message) => message.renderKey !== assistantRenderKey);
-          const withHistory = appendUnseenAssistantTurns(
-            mergeTurnQuestions(withoutPlaceholder, turns),
-            messagesFromTurns(turns as readonly PersistedTurn[]),
-          );
-          if (withHistory.length > withoutPlaceholder.length) return withHistory;
-          return [
-            ...withHistory,
-            {
-              role: "assistant" as const,
-              text: narration,
-              renderKey: assistantRenderKey,
-              state: "settled" as const,
-              activity: undefined,
-            },
-          ];
-        });
-      });
-      if (willContinue) {
-        // The follow-up turn continues on the row already in place: no removed
-        // row, no effect hop, and `busy` never drops in between (so the next
-        // card cannot flash before the turn hides it).
-        await send("read_only", "", { reuseAssistantRenderKey: assistantRenderKey, label: recordingLabel });
-      } else {
-        const narration = typeof payload?.narration === "string" && payload.narration.trim()
-          ? payload.narration.trim()
-          : "已记录你的选择。";
-        onMessagesChange?.([
-          { role: "assistant", text: narration },
-        ]);
-      }
-    } catch (caught) {
-      if (isAbortError(caught)) {
-        lastRunOutcome.current = "stopped";
-        setMessages((current) => current.map((message) => (
-          message.renderKey !== assistantRenderKey ? message : {
-            ...message,
-            state: "settled" as const,
-            failed: false,
-            stopped: true,
-            activity: undefined,
-          }
-        )));
-        return;
-      }
-      lastRunOutcome.current = "failed";
-      rollBackFailedChoice();
-      setError(RECTIFICATION_CHOICE_SUBMIT_FAILED_COPY);
-      await reloadAfterFailedChoice();
-    } finally {
-      if (runAbort.current === abortController) runAbort.current = null;
-      if (lastRunOutcome.current === null) lastRunOutcome.current = "succeeded";
-      setPending(false);
-    }
-  }, [
+    override?: RectificationStructuredChoiceOverride,
+  ) => runRectificationStructuredChoice({
+    caseId,
+    sessionId,
+    busy,
+    readonly,
+    choiceCard,
+    currentQuestion,
+    keyCounter,
+    runAbort,
+    lastRunOutcome,
+    conversationAnchor,
+    actionIdForChoice,
+    setError,
+    setMessages,
+    setChoiceNonce,
+    setNextUserActionId,
+    setPending,
+    beginLiveRun,
+    loadCaseSnapshot,
+    send,
+    onCompleted,
+    onMessagesChange,
+    onProfileIncomplete,
+  }, action, optionId, override), [
     beginLiveRun,
     caseId,
     choiceCard,
@@ -1340,152 +361,46 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
     void send("opening", "");
   }, [initialTurns.length, onOpeningConsumed, readonly, send, shouldStartOpening]);
 
-  const acceptCandidate = useCallback(async (candidateId: string) => {
-    if (!candidateResult || acceptingCandidateId || busy || readonly) return;
-    setError("");
-    setAcceptingCandidateId(candidateId);
-    setPending(true);
-    // Adoption is a server round trip followed by an agent turn; the reader sees
-    // one live row for the whole of it instead of a greyed button.
-    const candidateTime = candidateResult.candidates.find((candidate) => candidate.candidateId === candidateId)?.time ?? "";
-    const adoptingLabel = rectificationAdoptingLabel(candidateTime);
-    keyCounter.current += 1;
-    const assistantRenderKey = `v9-adopt-assistant-${keyCounter.current}`;
-    beginLiveRun(adoptingLabel);
-    setMessages((current) => [
-      ...current,
-      {
-        role: "assistant",
-        text: "",
-        renderKey: assistantRenderKey,
-        state: "thinking",
-        activityTrace: emptyActivityTrace(),
-        activity: { phase: "evidence-validation", label: adoptingLabel, startedAt: Date.now() },
-      },
-    ]);
-    conversationAnchor.pinLatestTurn();
-    const abortController = new AbortController();
-    runAbort.current = abortController;
-    try {
-      const response = await fetch(
-        `/api/rectification/cases/${encodeURIComponent(caseId)}/candidates/accept`,
-        {
-          method: "POST",
-          headers: { "content-type": "application/json" },
-          signal: abortController.signal,
-          body: JSON.stringify({
-            sessionId,
-            resultId: candidateResult.resultId,
-            candidateId,
-            requestId: globalThis.crypto.randomUUID(),
-            mode: "range",
-          }),
-        },
-      );
-      const payload = await response.json().catch(() => null);
-      if (!response.ok || payload?.ok !== true || payload?.status !== "accepted") {
-        throw new Error(payload?.error || payload?.message || "暂时无法采用该候选时间");
-      }
-      setCandidateResult((current) => {
-        if (!current) return current;
-        const selectedTime = typeof payload.saved_time === "string" ? payload.saved_time.slice(0, 5) : current.selectedTime;
-        const next = {
-          ...current,
-          selectedTime,
-          selectionKind: "user_accepted" as const,
-        };
-        const houseTable = workingRectificationHouseTable(next);
-        const recastMeaning = natalRecastMeaning(houseTable);
-        return {
-          ...next,
-          houseTable: houseTable ?? current.houseTable,
-          natalRecast: houseTable && recastMeaning
-            ? {
-                time: houseTable.time,
-                lagna: houseTable.lagna,
-                user_meaning: recastMeaning,
-                unique_minute_claim: false as const,
-                confirmation_allowed: false as const,
-              }
-            : current.natalRecast,
-        };
-      });
-      setSavedTime(payload.saved_time);
-      setSavedStatus("accepted");
-      onSaved?.(payload.saved_time, "accepted");
-      onCompleted?.();
-      await loadCaseSnapshot();
-      await send("read_only", "", { reuseAssistantRenderKey: assistantRenderKey, label: adoptingLabel });
-    } catch (caught) {
-      if (isAbortError(caught)) {
-        lastRunOutcome.current = "stopped";
-        setMessages((current) => current.map((message) => (
-          message.renderKey !== assistantRenderKey ? message : {
-            ...message,
-            state: "settled" as const,
-            failed: false,
-            stopped: true,
-            activity: undefined,
-          }
-        )));
-        return;
-      }
-      lastRunOutcome.current = "failed";
-      setMessages((current) => current.filter((message) => message.renderKey !== assistantRenderKey));
-      setError(caught instanceof Error ? caught.message : "暂时无法采用该候选时间");
-    } finally {
-      if (runAbort.current === abortController) runAbort.current = null;
-      if (lastRunOutcome.current === null) lastRunOutcome.current = "succeeded";
-      setAcceptingCandidateId(null);
-      setPending(false);
-    }
-  }, [acceptingCandidateId, beginLiveRun, busy, candidateResult, caseId, loadCaseSnapshot, onCompleted, onSaved, readonly, send, sessionId, setPending]);
+  const acceptCandidate = useCallback(async (candidateId: string) => runRectificationCandidateAccept({
+    caseId,
+    sessionId,
+    busy,
+    readonly,
+    candidateResult,
+    acceptingCandidateId,
+    keyCounter,
+    runAbort,
+    lastRunOutcome,
+    conversationAnchor,
+    setError,
+    setMessages,
+    setAcceptingCandidateId,
+    setCandidateResult,
+    setSavedTime,
+    setSavedStatus,
+    setPending,
+    beginLiveRun,
+    loadCaseSnapshot,
+    send,
+    onCompleted,
+    onSaved,
+  }, candidateId), [acceptingCandidateId, beginLiveRun, busy, candidateResult, caseId, loadCaseSnapshot, onCompleted, onSaved, readonly, send, sessionId, setPending]);
 
   async function copyMessage(message: RenderMessage) {
-    try {
-      await navigator.clipboard.writeText(copyTextForMessage(message.text, message.question));
-      setCopiedMessageKey(message.renderKey);
-      window.setTimeout(() => setCopiedMessageKey((current) => (
-        current === message.renderKey ? null : current
-      )), 1_500);
-    } catch {
-      // Clipboard permission failures must not interrupt the conversation.
-    }
+    await copyRectificationMessage({ setCopiedMessageKey }, message);
   }
 
   async function regenerateMessage(message: RenderMessage) {
-    if (!message.turnId || regeneratingMessageKey || busy || readonly) return;
-    setError("");
-    setRegeneratingMessageKey(message.renderKey);
-    const previousText = message.text;
-    try {
-      const response = await fetch(
-        `/api/rectification/cases/${encodeURIComponent(caseId)}/turns/${encodeURIComponent(message.turnId)}/regenerate`,
-        {
-          method: "POST",
-          headers: { "content-type": "application/json" },
-          body: JSON.stringify({
-            sessionId,
-            requestId: globalThis.crypto.randomUUID(),
-          }),
-        },
-      );
-      const payload = await response.json().catch(() => null);
-      if (!response.ok || payload?.ok !== true || typeof payload.assistantMessage !== "string") {
-        throw new Error(payload?.message || payload?.error || "暂时无法重新生成回答");
-      }
-      const nextText = payload.assistantMessage;
-      setMessages((current) => current.map((item) => item.renderKey === message.renderKey
-        ? { ...item, text: nextText, state: "settled" }
-        : item));
-    } catch (caught) {
-      setMessages((current) => current.map((item) => item.renderKey === message.renderKey
-        ? { ...item, text: previousText, state: "settled" }
-        : item));
-      setError(caught instanceof Error ? caught.message : "暂时无法重新生成回答");
-    } finally {
-      setRegeneratingMessageKey((current) => current === message.renderKey ? null : current);
-    }
+    await regenerateRectificationMessage({
+      caseId,
+      sessionId,
+      busy,
+      readonly,
+      regeneratingMessageKey,
+      setError,
+      setMessages,
+      setRegeneratingMessageKey,
+    }, message);
   }
 
   async function submit(event: React.FormEvent) {
@@ -1500,189 +415,51 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
     await send("message", text);
   }
 
-  const latestRegeneratableKey = [...messages]
-    .reverse()
-    .find((message) => (
-      message.role === "assistant"
-      && message.state === "settled"
-      && !message.failed
-      && Boolean(message.turnId)
-      && Boolean(message.text)
-    ))?.renderKey;
-  const latestSettledAssistant = [...messages]
-    .reverse()
-    .find((message) => (
-      message.role === "assistant"
-      && message.state === "settled"
-      && !message.failed
-      && Boolean(message.text)
-    ));
-  const latestLiveQuestion = [...messages].reverse().find((message) => (
-    message.role === "assistant"
-    && message.question
-    && !questionIsAnswered(message.question)
-  ))?.question ?? null;
-  const showLiveChoiceCard = Boolean(
-    latestLiveQuestion
-    && latestLiveQuestion.options?.length === 4
-    && currentQuestion?.focus_id === latestLiveQuestion.focus_id
-    && choiceCard
-    && choiceCard.focus_id === latestLiveQuestion.focus_id
-    && (latestLiveQuestion.kind === "choice" || latestLiveQuestion.kind === "reverse_verify")
-    && !busy
-    && !readonly
-    && regeneratingMessageKey === null,
-  );
-  const canOfferCards = canShowRectificationSelectionCards(candidateResult);
-  // Cheap arithmetic over at most a dozen candidate minutes; recomputed with
-  // the render rather than memoised, matching the rest of this component.
-  const timelineView = buildRectificationTimeline({
+  const {
+    latestRegeneratableKey,
+    latestSettledAssistant,
+    showLiveChoiceCard,
+    timelineView,
+    nextOfferLock,
+    selectionCardMessageKey,
+    liveInterviewBlockingAdopt,
+    showSelectionCards,
+    showReadonlyRange,
+    collectSpokenPrompt,
+    liveQuestionOnMessages,
+    questionGap,
+    placedByKey,
+    showStandaloneQuestion,
+    verifiedIdleCopy,
+    conversationState,
+  } = deriveRectificationChatView({
+    messages,
+    busy,
+    readonly,
+    regeneratingMessageKey,
+    shouldStartOpening,
+    openingRequested,
+    acceptingCandidateId,
+    selectionOfferLock,
+    candidateResult,
+    currentQuestion,
+    questionSource,
+    choiceCard,
+    caseStatus,
+    caseSnapshotLoaded,
     searchWindow,
-    credibleRange: candidateResult?.credibleRange ?? null,
-    candidateTimes: candidateResult?.candidates.map((candidate) => candidate.time) ?? [],
-    inferenceMarks: candidateResult?.inferenceMarks ?? [],
-    stage: caseStage,
-    // The same call the board's title-row clock makes, on the same result, so
-    // the bar and `.rectification-board__clock` are one number by construction
-    // rather than by two code paths that happen to agree today.
-    workingTime: workingRectificationTime(candidateResult),
-    workingAdopted: Boolean(candidateResult?.selectedTime),
-    answeredProbeCount: candidateResult?.answeredProbeCount ?? null,
-    datedEventCount: candidateResult?.rangeDelivery?.event_count ?? null,
+    caseStage,
+    nextUserActionId,
+    interviewStopReason,
+    interviewSessionOutcome,
+    questionRetryAttempts,
+    savedTime,
   });
-  const persistedOfferKey = [...messages].reverse().find((message) => message.candidateOffer)?.renderKey;
-  const liveSelectionCardKey = persistedOfferKey
-    ?? (canOfferCards && !candidateResult?.selectedTime ? latestSettledAssistant?.renderKey : undefined);
   // Same render-time store update as seededTurns: the lock must be current
   // before this paint (BUG-620). A ref write here trips react-hooks/refs.
-  const nextOfferLock = nextSelectionCardLock(selectionOfferLock, {
-    resultId: candidateResult?.resultId,
-    key: liveSelectionCardKey,
-  });
   if (nextOfferLock !== selectionOfferLock) {
     setSelectionOfferLock(nextOfferLock);
   }
-  const selectionCardMessageKey = resolveSelectionCardMessageKey({
-    persistedOfferKey,
-    fallbackKey: latestSettledAssistant?.renderKey,
-    locked: nextOfferLock,
-    resultId: candidateResult?.resultId,
-    selectedTime: candidateResult?.selectedTime,
-    canOffer: canOfferCards,
-  });
-  // Adopt already has in-card “正在采用…” / “已采用”; hiding the whole card
-  // for `busy` is what made the three columns vanish on 「更像这个」.
-  const keepSelectionCardsWhileBusy = Boolean(
-    acceptingCandidateId || candidateResult?.selectedTime,
-  );
-  const liveInterviewBlockingAdopt = Boolean(
-    candidateResult
-    && !candidateResult.selectedTime
-    && messages.some((message) => (
-      interviewQuestionBlocksAdoptOffer(message.question, false)
-    )),
-  );
-  const showSelectionCards = Boolean(
-    candidateResult
-    && caseSnapshotLoaded
-    && (!busy || keepSelectionCardsWhileBusy)
-    && selectionCardMessageKey
-    && (canOfferCards || Boolean(candidateResult.selectedTime))
-  );
-  const showReadonlyRange = Boolean(
-    canShowRectificationReadonlyRange(candidateResult)
-    && latestSettledAssistant
-    && !showSelectionCards,
-  );
-  const collectSpokenPrompt = currentQuestion?.kind === "collect_spoken"
-    ? currentQuestion.prompt
-    : null;
-  const resumableCase = caseStatus !== null && isResumableStatus(caseStatus);
-  const deadChoice = interviewChoiceCardUnavailable({
-    questionKind: currentQuestion?.kind,
-    hasChoiceCard: Boolean(choiceCard),
-    questionId: currentQuestion?.question_id,
-  });
-  const liveQuestionOnMessages = Boolean(
-    latestSettledAssistant
-    && latestSettledAssistant.question
-    && currentQuestion
-    && latestSettledAssistant.question.focus_id === currentQuestion.focus_id
-    && !questionIsAnswered(latestSettledAssistant.question)
-    && !deadChoice,
-  );
-  // The gap between a settled turn and its next question has two visible
-  // states: `preparing` (one live timeline row, timed refetches) and
-  // `unavailable` (copy and a repair button) — never bare copy telling the
-  // reader to wait for the server. Collect-waiting is the training-gate gap:
-  // no next card, keep the case open, do not show 「没有拿到下一个问题」.
-  const collectWaiting = interviewCollectWaiting({
-    stopReason: interviewStopReason,
-    sessionOutcome: interviewSessionOutcome ?? candidateResult?.sessionOutcome ?? null,
-    questionMissing: currentQuestion === null,
-    offeringCards: showSelectionCards,
-  });
-  // BUG-917: the same judgement the message entry makes, read off the latest
-  // settled assistant message: a tap question nobody can answer any more.
-  const unansweredDeadChoiceOnMessages = Boolean(
-    latestSettledAssistant?.question
-    && (latestSettledAssistant.question.kind === "choice"
-      || latestSettledAssistant.question.kind === "reverse_verify")
-    && !latestSettledAssistant.question.answer_option
-    && (latestSettledAssistant.question.status === "active"
-      || latestSettledAssistant.question.status === "superseded")
-    && !liveQuestionOnMessages,
-  );
-  const questionGap = rectificationQuestionGapState({
-    liveQuestionVisible: liveQuestionOnMessages,
-    unansweredDeadChoice: unansweredDeadChoiceOnMessages,
-    questionMissing: currentQuestion === null,
-    questionLoadFailed: questionSource === "unavailable" || deadChoice,
-    questionPersisted: Boolean(currentQuestion?.prompt && questionSource === "focus") && !deadChoice,
-    offerAwaitingReader: showSelectionCards && !candidateResult?.selectedTime && currentQuestion === null,
-    nextUserActionId,
-    collectWaiting: collectWaiting && !deadChoice,
-    sessionOutcome: interviewSessionOutcome ?? candidateResult?.sessionOutcome ?? null,
-    stopReason: interviewStopReason,
-    deadChoice,
-    questionId: currentQuestion?.question_id ?? null,
-    hasChoiceCard: Boolean(choiceCard),
-    busy,
-    readonly,
-    regenerating: regeneratingMessageKey !== null,
-    snapshotLoaded: caseSnapshotLoaded,
-    resumableCase,
-    retryAttempts: questionRetryAttempts,
-    retryLimit: RECTIFICATION_QUESTION_RETRY_LIMIT,
-  });
-  // BUG-1046 (D3): the persisted question is drawn once. With an assistant
-  // message to carry it, it hangs there (BUG-678's intent) and other copies of
-  // the same focus come off; the standalone block is only the fallback when
-  // nothing can carry it. The gap state itself is unchanged.
-  const persistedTurnQuestion = questionGap === "persisted_question"
-    ? turnQuestionFromCurrent(currentQuestion, choiceCard)
-    : null;
-  const placedQuestion = persistedTurnQuestion
-    ? placePersistedQuestion(messages, persistedTurnQuestion, isSettledAssistantMessage)
-    : null;
-  const placedByKey = placedQuestion && placedQuestion.messages !== messages
-    ? new Map(placedQuestion.messages.map((message) => [message.renderKey, message]))
-    : null;
-  const showStandaloneQuestion = questionGap === "persisted_question"
-    && (placedQuestion ? placedQuestion.standalone : true);
-  const verifiedIdleCopy = questionGap === "verified_idle"
-    ? postAdoptVerifyDoneCopy(
-      savedTime,
-      messages.some((message) => message.question?.kind === "reverse_verify"),
-    )
-    : null;
-  const conversationState = rectificationConversationState({
-    messageCount: messages.length,
-    busy,
-    readonly,
-    shouldStartOpening,
-    openingStarted: openingRequested,
-  });
   // Question recovery: the turn already refetched once on completion; while
   // the gap is `preparing`, refetch on a timer up to the retry limit, then
   // hand the reader a repair button. Attempts reset once a question arrives
@@ -1697,54 +474,20 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
     },
   });
   async function refetchQuestion() {
-    await loadCaseSnapshot((turns) => {
-      setMessages((current) => applySnapshotTurnsToMessages(
-        current,
-        turns,
-        (incoming) => messagesFromTurns(incoming as readonly PersistedTurn[]),
-      ));
-    });
+    await refetchRectificationQuestion({ loadCaseSnapshot, setMessages });
   }
   async function repairQuestion() {
-    if (questionRepairing || questionRepairAttempts >= RECTIFICATION_QUESTION_REPAIR_LIMIT) return;
-    setQuestionRepairing(true);
-    try {
-      const response = await fetch(
-        `/api/rectification/cases/${encodeURIComponent(caseId)}/repair-exit`,
-        {
-          method: "POST",
-          headers: { "content-type": "application/json" },
-          cache: "no-store",
-          body: JSON.stringify({ sessionId }),
-        },
-      );
-      const payload = await response.json().catch(() => null);
-      if (response.ok && payload) {
-        startTransition(() => {
-          applyCaseSnapshot(payload);
-        });
-        const recovered = Boolean(
-          currentQuestionFromSnapshot(payload.current_question)
-          || parseRectificationChoiceCard(payload.choice_card)
-          || payload.case?.accepted_time
-          || payload.case?.confirmed_time
-        );
-        if (!recovered) setQuestionRepairAttempts((current) => current + 1);
-      } else {
-        await loadCaseSnapshot((turns) => {
-          setMessages((current) => applySnapshotTurnsToMessages(
-            current,
-            turns,
-            (incoming) => messagesFromTurns(incoming as readonly PersistedTurn[]),
-          ));
-        });
-        setQuestionRepairAttempts((current) => current + 1);
-      }
-    } catch {
-      setQuestionRepairAttempts((current) => current + 1);
-    } finally {
-      setQuestionRepairing(false);
-    }
+    await repairRectificationQuestion({
+      caseId,
+      sessionId,
+      questionRepairing,
+      questionRepairAttempts,
+      setQuestionRepairing,
+      setQuestionRepairAttempts,
+      applyCaseSnapshot,
+      loadCaseSnapshot,
+      setMessages,
+    });
   }
 
   // A Case with no turns and no automatic first turn (the server never starts
@@ -1894,70 +637,21 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
               </div>
             );
           })}
-          {showStandaloneQuestion && currentQuestion?.prompt && (
-            <div className="rectification-message-wrap rectification-message-entry" data-testid="persisted-question">
-              <div className="rectification-message-question is-standalone">
-                {persistedQuestionSurface({
-                  questionKind: currentQuestion.kind,
-                  hasChoiceCard: Boolean(choiceCard),
-                  questionPersisted: true,
-                }) === "choice_card" && choiceCard ? (
-                  <>
-                    <p className="rectification-message-question__prompt">{currentQuestion.prompt}</p>
-                    <RectificationChoiceCard
-                      key={`${choiceCard.question_id}:${choiceNonce}:persisted`}
-                      variant="embedded"
-                      card={choiceCard}
-                      pending={busy}
-                      disabled={busy || readonly}
-                      selectedKey=""
-                      onSelect={submitChoice}
-                      onStop={submitStop}
-                    />
-                  </>
-                ) : (
-                  <p className="rectification-message-question__prompt">{currentQuestion.prompt}</p>
-                )}
-              </div>
-            </div>
-          )}
-          {questionGap === "preparing" && (
-            <div className="rectification-message-wrap rectification-message-entry rectification-question-gap">
-              <ConsultationTimelineLiveRow id="question-preparing" label={RECTIFICATION_QUESTION_PREPARING_LABEL} />
-            </div>
-          )}
-          {questionGap === "delivered" && !showSelectionCards && (
-            <p className="rectification-pending-note" role="status">
-              {RECTIFICATION_DELIVERED_COPY}
-            </p>
-          )}
-          {snapshotFailure && (
-            <div className="rectification-message-wrap rectification-message-entry rectification-question-gap" role="status">
-              <p className="rectification-question-gap__copy">{RECTIFICATION_SNAPSHOT_UNAVAILABLE_COPY}</p>
-              <Button type="button" variant="outline" onClick={() => void refetchQuestion()}>
-                {RECTIFICATION_SNAPSHOT_RETRY_LABEL}
-              </Button>
-            </div>
-          )}
-          {questionGap === "unavailable" && !snapshotFailure && (
-            <div className="rectification-message-wrap rectification-message-entry rectification-question-gap" role="status">
-              {questionRepairAttempts >= RECTIFICATION_QUESTION_REPAIR_LIMIT ? (
-                <p className="rectification-question-gap__copy">{RECTIFICATION_QUESTION_REPAIR_FAILED_COPY}</p>
-              ) : (
-                <>
-                  <p className="rectification-question-gap__copy">{RECTIFICATION_QUESTION_UNAVAILABLE_COPY}</p>
-                  <Button type="button" variant="outline" onClick={() => void repairQuestion()} disabled={questionRepairing}>
-                    {RECTIFICATION_QUESTION_RELOAD_LABEL}
-                  </Button>
-                </>
-              )}
-            </div>
-          )}
-          {questionGap === "verified_idle" && verifiedIdleCopy && !showSelectionCards && (
-            <p className="rectification-pending-note" role="status">
-              {verifiedIdleCopy}
-            </p>
-          )}
+          <RectificationQuestionGapNotices
+            view={{ showStandaloneQuestion, questionGap, showSelectionCards, verifiedIdleCopy }}
+            currentQuestion={currentQuestion}
+            choiceCard={choiceCard}
+            choiceNonce={choiceNonce}
+            busy={busy}
+            readonly={readonly}
+            snapshotFailure={snapshotFailure}
+            questionRepairAttempts={questionRepairAttempts}
+            questionRepairing={questionRepairing}
+            submitChoice={submitChoice}
+            submitStop={submitStop}
+            refetchQuestion={refetchQuestion}
+            repairQuestion={repairQuestion}
+          />
           {savedTime && savedStatus === "confirmed" && (
             <p className="rectification-saved" role="status">
               已确认校正时间：{savedTime}
diff --git a/frontend/src/components/rectification-question-gap-notices.tsx b/frontend/src/components/rectification-question-gap-notices.tsx
new file mode 100644
index 00000000..e3b93c8a
--- /dev/null
+++ b/frontend/src/components/rectification-question-gap-notices.tsx
@@ -0,0 +1,151 @@
+"use client";
+
+import {
+  RECTIFICATION_DELIVERED_COPY,
+  RECTIFICATION_QUESTION_PREPARING_LABEL,
+  RECTIFICATION_QUESTION_RELOAD_LABEL,
+  RECTIFICATION_QUESTION_REPAIR_FAILED_COPY,
+  RECTIFICATION_QUESTION_REPAIR_LIMIT,
+  RECTIFICATION_QUESTION_UNAVAILABLE_COPY,
+  RECTIFICATION_SNAPSHOT_RETRY_LABEL,
+  RECTIFICATION_SNAPSHOT_UNAVAILABLE_COPY,
+  persistedQuestionSurface,
+  rectificationReadonlyRangeCopy,
+  type RectificationSnapshotFailure,
+} from "@/lib/rectification-surface-state";
+import type { ChoiceKey, RectificationChoiceCard as ChoiceCardModel } from "@/lib/rectification-agentic/v9/choice-card";
+import type { CurrentQuestionModel } from "@/lib/rectification-chat-snapshot";
+import type { RectificationChatView } from "@/lib/rectification-chat-view";
+import { Button } from "@/components/ui/button";
+import { ConsultationTimelineLiveRow } from "./consultation-run-timeline";
+import { RectificationChoiceCard } from "./rectification-choice-card";
+
+export function RectificationReadonlyRange({
+  range,
+  sessionOutcome,
+  discriminatingEventProbes,
+  contrastProbes,
+}: Readonly<{
+  range: readonly [string, string];
+  sessionOutcome: string | null;
+  discriminatingEventProbes: unknown;
+  contrastProbes: unknown;
+}>) {
+  return (
+    <p className="rectification-readonly-range" role="status">
+      {rectificationReadonlyRangeCopy({
+        range,
+        sessionOutcome,
+        discriminatingEventProbes,
+        contrastProbes,
+      })}
+    </p>
+  );
+}
+
+/**
+ * The blocks under the transcript that stand in for a missing next question:
+ * the standalone persisted question (only when no assistant message can carry
+ * it), the preparing row, the delivered note, the snapshot-failure retry, the
+ * repair button, and the verified-idle note. Moved out of
+ * RectificationAgenticChat unchanged (TASK-rectification-code-split-20260926).
+ */
+export function RectificationQuestionGapNotices({
+  view,
+  currentQuestion,
+  choiceCard,
+  choiceNonce,
+  busy,
+  readonly,
+  snapshotFailure,
+  questionRepairAttempts,
+  questionRepairing,
+  submitChoice,
+  submitStop,
+  refetchQuestion,
+  repairQuestion,
+}: Readonly<{
+  view: Pick<RectificationChatView, "showStandaloneQuestion" | "questionGap" | "showSelectionCards" | "verifiedIdleCopy">;
+  currentQuestion: CurrentQuestionModel | null;
+  choiceCard: ChoiceCardModel | null;
+  choiceNonce: number;
+  busy: boolean;
+  readonly: boolean;
+  snapshotFailure: RectificationSnapshotFailure | null;
+  questionRepairAttempts: number;
+  questionRepairing: boolean;
+  submitChoice: (key: ChoiceKey) => void;
+  submitStop: () => void;
+  refetchQuestion: () => Promise<void>;
+  repairQuestion: () => Promise<void>;
+}>) {
+  const { showStandaloneQuestion, questionGap, showSelectionCards, verifiedIdleCopy } = view;
+  return (
+    <>
+      {showStandaloneQuestion && currentQuestion?.prompt && (
+        <div className="rectification-message-wrap rectification-message-entry" data-testid="persisted-question">
+          <div className="rectification-message-question is-standalone">
+            {persistedQuestionSurface({
+              questionKind: currentQuestion.kind,
+              hasChoiceCard: Boolean(choiceCard),
+              questionPersisted: true,
+            }) === "choice_card" && choiceCard ? (
+              <>
+                <p className="rectification-message-question__prompt">{currentQuestion.prompt}</p>
+                <RectificationChoiceCard
+                  key={`${choiceCard.question_id}:${choiceNonce}:persisted`}
+                  variant="embedded"
+                  card={choiceCard}
+                  pending={busy}
+                  disabled={busy || readonly}
+                  selectedKey=""
+                  onSelect={submitChoice}
+                  onStop={submitStop}
+                />
+              </>
+            ) : (
+              <p className="rectification-message-question__prompt">{currentQuestion.prompt}</p>
+            )}
+          </div>
+        </div>
+      )}
+      {questionGap === "preparing" && (
+        <div className="rectification-message-wrap rectification-message-entry rectification-question-gap">
+          <ConsultationTimelineLiveRow id="question-preparing" label={RECTIFICATION_QUESTION_PREPARING_LABEL} />
+        </div>
+      )}
+      {questionGap === "delivered" && !showSelectionCards && (
+        <p className="rectification-pending-note" role="status">
+          {RECTIFICATION_DELIVERED_COPY}
+        </p>
+      )}
+      {snapshotFailure && (
+        <div className="rectification-message-wrap rectification-message-entry rectification-question-gap" role="status">
+          <p className="rectification-question-gap__copy">{RECTIFICATION_SNAPSHOT_UNAVAILABLE_COPY}</p>
+          <Button type="button" variant="outline" onClick={() => void refetchQuestion()}>
+            {RECTIFICATION_SNAPSHOT_RETRY_LABEL}
+          </Button>
+        </div>
+      )}
+      {questionGap === "unavailable" && !snapshotFailure && (
+        <div className="rectification-message-wrap rectification-message-entry rectification-question-gap" role="status">
+          {questionRepairAttempts >= RECTIFICATION_QUESTION_REPAIR_LIMIT ? (
+            <p className="rectification-question-gap__copy">{RECTIFICATION_QUESTION_REPAIR_FAILED_COPY}</p>
+          ) : (
+            <>
+              <p className="rectification-question-gap__copy">{RECTIFICATION_QUESTION_UNAVAILABLE_COPY}</p>
+              <Button type="button" variant="outline" onClick={() => void repairQuestion()} disabled={questionRepairing}>
+                {RECTIFICATION_QUESTION_RELOAD_LABEL}
+              </Button>
+            </>
+          )}
+        </div>
+      )}
+      {questionGap === "verified_idle" && verifiedIdleCopy && !showSelectionCards && (
+        <p className="rectification-pending-note" role="status">
+          {verifiedIdleCopy}
+        </p>
+      )}
+    </>
+  );
+}
diff --git a/frontend/src/hooks/use-rectification-board-layout.ts b/frontend/src/hooks/use-rectification-board-layout.ts
new file mode 100644
index 00000000..9eccce5f
--- /dev/null
+++ b/frontend/src/hooks/use-rectification-board-layout.ts
@@ -0,0 +1,53 @@
+"use client";
+
+import { useCallback, useEffect, useId, useLayoutEffect, useRef, useState } from "react";
+import {
+  diffRectificationBoard,
+  RECTIFICATION_BOARD_SPLIT_MIN_PX,
+} from "@/lib/rectification-board-model";
+import type { CandidateResult } from "@/lib/rectification-chat-snapshot";
+
+/**
+ * Board layout of the rectification surface: compact (drawer) vs split view,
+ * the drawer's open state, and the change highlight between two candidate
+ * results. Moved out of RectificationAgenticChat unchanged
+ * (TASK-rectification-code-split-20260926).
+ */
+export function useRectificationBoardLayout(candidateResult: CandidateResult) {
+  const previousBoardResult = useRef<CandidateResult>(null);
+  const [compactBoard, setCompactBoard] = useState(false);
+  const [boardOpen, setBoardOpen] = useState(false);
+  const [boardDiff, setBoardDiff] = useState(() => diffRectificationBoard(null, null));
+  const boardId = useId();
+  const boardTitleId = useId();
+
+  useLayoutEffect(() => {
+    const query = window.matchMedia(`(max-width: ${RECTIFICATION_BOARD_SPLIT_MIN_PX - 1}px)`);
+    const update = () => {
+      const nextCompact = query.matches;
+      setCompactBoard(nextCompact);
+      if (!nextCompact) setBoardOpen(false);
+    };
+    update();
+    query.addEventListener("change", update);
+    return () => query.removeEventListener("change", update);
+  }, []);
+
+  useEffect(() => {
+    setBoardDiff(diffRectificationBoard(previousBoardResult.current, candidateResult));
+    previousBoardResult.current = candidateResult;
+  }, [candidateResult]);
+
+  const closeBoard = useCallback(() => setBoardOpen(false), []);
+  const toggleBoard = useCallback(() => setBoardOpen((current) => !current), []);
+
+  return {
+    compactBoard,
+    boardOpen,
+    boardDiff,
+    boardId,
+    boardTitleId,
+    closeBoard,
+    toggleBoard,
+  };
+}
diff --git a/frontend/src/hooks/use-rectification-case-snapshot.ts b/frontend/src/hooks/use-rectification-case-snapshot.ts
new file mode 100644
index 00000000..ef001ad4
--- /dev/null
+++ b/frontend/src/hooks/use-rectification-case-snapshot.ts
@@ -0,0 +1,211 @@
+"use client";
+
+import { startTransition, useCallback, useLayoutEffect, useRef, useState } from "react";
+import {
+  parseRectificationCandidateResult,
+} from "@/lib/rectification-candidate-result";
+import {
+  isAbortError,
+  searchWindowFromSnapshot,
+  caseStageFromSnapshot,
+  interviewStopReasonFromSnapshot,
+  interviewSessionOutcomeFromSnapshot,
+  birthTimeSourceFromSnapshot,
+  type RectificationCaseSnapshotPayload,
+  type RectificationSnapshotFailure,
+} from "@/lib/rectification-surface-state";
+import type { RectificationTimelineStage } from "@/lib/rectification-timeline-scale";
+import { isRectificationCaseStatus, type RectificationCaseStatus } from "@/lib/rectification-agentic/v9/case-status";
+import { parseRectificationChoiceCard, type RectificationChoiceCard as ChoiceCardModel } from "@/lib/rectification-agentic/v9/choice-card";
+import { snapshotTurns } from "@/lib/rectification-chat-messages";
+import {
+  caseSnapshotState,
+  currentQuestionFromSnapshot,
+  questionSourceFromSnapshot,
+  type CandidateResult,
+  type CurrentQuestionModel,
+} from "@/lib/rectification-chat-snapshot";
+
+/**
+ * Case snapshot sync for the rectification chat surface: the state that the
+ * persisted Candidate Snapshot API owns (candidate, current question, choice
+ * card, saved time, timeline window / stage, interview outcome), the
+ * question-recovery counters that reset when a question arrives, and the one
+ * snapshot read in flight. Moved out of RectificationAgenticChat unchanged
+ * (TASK-rectification-code-split-20260926).
+ */
+export function useRectificationCaseSnapshot({
+  caseId,
+  sessionId,
+  initialSnapshot,
+}: Readonly<{
+  caseId: string;
+  sessionId: string;
+  initialSnapshot: RectificationCaseSnapshotPayload | null;
+}>) {
+  const [resultNotice, setResultNotice] = useState(initialSnapshot?.case?.result_notice ?? null);
+  const [canRecompare, setCanRecompare] = useState(initialSnapshot?.case?.result_identity?.can_recompare === true);
+  const [savedTime, setSavedTime] = useState<string | null>(() => caseSnapshotState(initialSnapshot)?.savedTime ?? null);
+  const [savedStatus, setSavedStatus] = useState<"accepted" | "confirmed" | null>(() => caseSnapshotState(initialSnapshot)?.savedStatus ?? null);
+  const [candidateResult, setCandidateResult] = useState<CandidateResult>(() => caseSnapshotState(initialSnapshot)?.candidate ?? null);
+  const [choiceCard, setChoiceCard] = useState<ChoiceCardModel | null>(() => caseSnapshotState(initialSnapshot)?.choice ?? null);
+  const [currentQuestion, setCurrentQuestion] = useState<CurrentQuestionModel | null>(() => caseSnapshotState(initialSnapshot)?.question ?? null);
+  const [questionSource, setQuestionSource] = useState<"focus" | "unavailable" | null>(() => caseSnapshotState(initialSnapshot)?.questionSource ?? null);
+  const [caseStatus, setCaseStatus] = useState<RectificationCaseStatus | null>(() => caseSnapshotState(initialSnapshot)?.caseStatus ?? null);
+  const [searchWindow, setSearchWindow] = useState<readonly [string, string] | null>(() => caseSnapshotState(initialSnapshot)?.searchWindow ?? null);
+  const [caseStage, setCaseStage] = useState<RectificationTimelineStage | null>(() => caseSnapshotState(initialSnapshot)?.stage ?? null);
+  const [nextUserActionId, setNextUserActionId] = useState<string | null>(() => caseSnapshotState(initialSnapshot)?.nextUserActionId ?? null);
+  const [interviewStopReason, setInterviewStopReason] = useState<string | null>(() => caseSnapshotState(initialSnapshot)?.interviewStopReason ?? null);
+  const [interviewSessionOutcome, setInterviewSessionOutcome] = useState<string | null>(() => caseSnapshotState(initialSnapshot)?.interviewSessionOutcome ?? null);
+  const [birthTimeSource, setBirthTimeSource] = useState(() => caseSnapshotState(initialSnapshot)?.birthTimeSource ?? birthTimeSourceFromSnapshot(initialSnapshot));
+  const [caseSnapshotLoaded, setCaseSnapshotLoaded] = useState(initialSnapshot !== null);
+  const [questionRetryAttempts, setQuestionRetryAttempts] = useState(0);
+  const [questionRepairAttempts, setQuestionRepairAttempts] = useState(0);
+  const [questionRepairing, setQuestionRepairing] = useState(false);
+  const [snapshotFailure, setSnapshotFailure] = useState<RectificationSnapshotFailure | null>(null);
+  const snapshotAbort = useRef<AbortController | null>(null);
+  const currentQuestionRef = useRef(currentQuestion);
+
+  useLayoutEffect(() => {
+    currentQuestionRef.current = currentQuestion;
+  }, [currentQuestion]);
+
+  // Candidate snapshot comes from the persisted Candidate Snapshot API, never
+  // from parsing agent text or hidden sentinels.
+  const applyCaseSnapshot = useCallback((payload: RectificationCaseSnapshotPayload | {
+    latest_result?: unknown;
+    current_question?: unknown;
+    choice_card?: unknown;
+    step_state?: unknown;
+    turns?: unknown;
+    question_source?: unknown;
+    next_user_action?: { id?: unknown };
+    interview?: { stop_reason?: unknown; session_outcome?: unknown };
+    case?: {
+      status?: unknown;
+      accepted_time?: unknown;
+      confirmed_time?: unknown;
+      candidate_range?: unknown;
+      stage?: unknown;
+    };
+  } | null) => {
+    if (!payload) return;
+    const snapshot = payload as RectificationCaseSnapshotPayload;
+    setResultNotice(snapshot.case?.result_notice ?? null);
+    setCanRecompare(snapshot.case?.result_identity?.can_recompare === true);
+    const nextCandidate = parseRectificationCandidateResult(payload.latest_result);
+    const nextQuestion = currentQuestionFromSnapshot(payload.current_question);
+    const nextChoice = parseRectificationChoiceCard(payload.choice_card);
+    const nextCaseStatus = isRectificationCaseStatus(payload.case?.status)
+      ? payload.case.status
+      : null;
+    const acceptedTime = typeof payload.case?.accepted_time === "string" ? payload.case.accepted_time : null;
+    const confirmedTime = typeof payload.case?.confirmed_time === "string" ? payload.case.confirmed_time : null;
+    const nextActionId = typeof payload.next_user_action?.id === "string"
+      ? payload.next_user_action.id.trim()
+      : "";
+    // Only overwrite when the payload actually carries them: a snapshot without
+    // a window should leave the timeline showing the last known one rather than
+    // dropping to the skeleton mid-session.
+    const nextWindow = searchWindowFromSnapshot(payload.case?.candidate_range);
+    if (nextWindow) setSearchWindow(nextWindow);
+    const nextStage = caseStageFromSnapshot(payload.case?.stage);
+    if (nextStage) setCaseStage(nextStage);
+    setCandidateResult(nextCandidate);
+    setCurrentQuestion(nextQuestion);
+    setQuestionSource(questionSourceFromSnapshot(payload.question_source));
+    setChoiceCard(nextChoice);
+    setCaseStatus(nextCaseStatus);
+    setNextUserActionId(nextActionId || null);
+    setInterviewStopReason(interviewStopReasonFromSnapshot(snapshot));
+    setInterviewSessionOutcome(interviewSessionOutcomeFromSnapshot(snapshot));
+    setBirthTimeSource(birthTimeSourceFromSnapshot(snapshot));
+    setCaseSnapshotLoaded(true);
+    if (nextQuestion || nextChoice || acceptedTime || confirmedTime) {
+      setQuestionRepairAttempts(0);
+    }
+    if (confirmedTime) {
+      setSavedTime(confirmedTime);
+      setSavedStatus("confirmed");
+    } else if (acceptedTime) {
+      setSavedTime(acceptedTime);
+      setSavedStatus("accepted");
+    }
+  }, []);
+
+  const loadCaseSnapshot = useCallback(async (
+    mergeMessages?: (turns: readonly unknown[]) => void,
+  ): Promise<{
+    question: CurrentQuestionModel | null;
+    turns: readonly unknown[];
+  } | null | undefined> => {
+    snapshotAbort.current?.abort();
+    const controller = new AbortController();
+    snapshotAbort.current = controller;
+    try {
+      const response = await fetch(
+        `/api/rectification/cases/${encodeURIComponent(caseId)}?sessionId=${encodeURIComponent(sessionId)}`,
+        { cache: "no-store", signal: controller.signal },
+      );
+      if (controller.signal.aborted) return undefined;
+      if (!response.ok) {
+        setSnapshotFailure({ status: response.status });
+        return undefined;
+      }
+      const payload = await response.json().catch(() => null);
+      if (controller.signal.aborted) return undefined;
+      const turns = snapshotTurns(payload);
+      startTransition(() => {
+        setSnapshotFailure(null);
+        applyCaseSnapshot(payload);
+        mergeMessages?.(turns);
+      });
+      return {
+        question: currentQuestionFromSnapshot(payload?.current_question),
+        turns,
+      };
+    } catch (error) {
+      if (isAbortError(error) || controller.signal.aborted) return undefined;
+      setSnapshotFailure({ status: "network" });
+      return undefined;
+    } finally {
+      if (snapshotAbort.current === controller) snapshotAbort.current = null;
+    }
+  }, [applyCaseSnapshot, caseId, sessionId]);
+
+  return {
+    resultNotice,
+    canRecompare,
+    savedTime,
+    setSavedTime,
+    savedStatus,
+    setSavedStatus,
+    candidateResult,
+    setCandidateResult,
+    choiceCard,
+    currentQuestion,
+    questionSource,
+    caseStatus,
+    searchWindow,
+    caseStage,
+    nextUserActionId,
+    setNextUserActionId,
+    interviewStopReason,
+    interviewSessionOutcome,
+    birthTimeSource,
+    caseSnapshotLoaded,
+    questionRetryAttempts,
+    setQuestionRetryAttempts,
+    questionRepairAttempts,
+    setQuestionRepairAttempts,
+    questionRepairing,
+    setQuestionRepairing,
+    snapshotFailure,
+    snapshotAbort,
+    currentQuestionRef,
+    applyCaseSnapshot,
+    loadCaseSnapshot,
+  };
+}
+
+export type RectificationCaseSnapshotSync = ReturnType<typeof useRectificationCaseSnapshot>;
diff --git a/frontend/src/hooks/use-rectification-live-activity.ts b/frontend/src/hooks/use-rectification-live-activity.ts
new file mode 100644
index 00000000..d50c45e1
--- /dev/null
+++ b/frontend/src/hooks/use-rectification-live-activity.ts
@@ -0,0 +1,66 @@
+"use client";
+
+import { useCallback, useEffect, useRef, type Dispatch, type SetStateAction } from "react";
+import { rectificationLiveProgressLabel } from "@/lib/rectification-activity-labels";
+import type { RenderMessage } from "@/components/rectification-message-entry";
+
+/**
+ * The live working row's label clock: when the run and the current step
+ * started, which tool is running, and the 4-second tick that refreshes the
+ * elapsed-time label while a turn is busy. Moved out of
+ * RectificationAgenticChat unchanged (TASK-rectification-code-split-20260926).
+ */
+export function useRectificationLiveActivity({
+  busy,
+  setMessages,
+}: Readonly<{
+  busy: boolean;
+  setMessages: Dispatch<SetStateAction<RenderMessage[]>>;
+}>) {
+  const runStartedAtRef = useRef(0);
+  const stepStartedAtRef = useRef(0);
+  const liveToolRef = useRef<string | null>(null);
+  const liveBaseLabelRef = useRef("正在处理…");
+
+  const beginLiveRun = useCallback((baseLabel: string) => {
+    const now = Date.now();
+    runStartedAtRef.current = now;
+    stepStartedAtRef.current = now;
+    liveToolRef.current = null;
+    liveBaseLabelRef.current = baseLabel;
+  }, []);
+
+  const rememberLiveActivity = useCallback((baseLabel: string, tool: string | null = liveToolRef.current) => {
+    if (liveBaseLabelRef.current !== baseLabel) {
+      liveBaseLabelRef.current = baseLabel;
+      stepStartedAtRef.current = Date.now();
+    }
+    liveToolRef.current = tool;
+    return rectificationLiveProgressLabel({
+      tool,
+      baseLabel,
+      stepStartedAt: stepStartedAtRef.current,
+      runStartedAt: runStartedAtRef.current,
+    });
+  }, []);
+
+  useEffect(() => {
+    if (!busy) return;
+    const id = window.setInterval(() => {
+      const label = rectificationLiveProgressLabel({
+        tool: liveToolRef.current,
+        baseLabel: liveBaseLabelRef.current,
+        stepStartedAt: stepStartedAtRef.current,
+        runStartedAt: runStartedAtRef.current,
+      });
+      setMessages((current) => current.map((message) => {
+        if (message.state !== "thinking" && message.state !== "streaming") return message;
+        if (!message.activity || message.activity.label === label) return message;
+        return { ...message, activity: { ...message.activity, label } };
+      }));
+    }, 4000);
+    return () => window.clearInterval(id);
+  }, [busy]);
+
+  return { beginLiveRun, rememberLiveActivity };
+}
diff --git a/frontend/src/lib/rectification-chat-accept-run.ts b/frontend/src/lib/rectification-chat-accept-run.ts
new file mode 100644
index 00000000..d29d8414
--- /dev/null
+++ b/frontend/src/lib/rectification-chat-accept-run.ts
@@ -0,0 +1,183 @@
+/**
+ * Adopting a candidate minute from the range delivery card: one live row for
+ * the accept POST and the agent turn that follows on it, the working house
+ * table recast from the adopted minute, and the stop / fail branches. Moved
+ * out of RectificationAgenticChat's `acceptCandidate` unchanged
+ * (TASK-rectification-code-split-20260926). A parameter function: the
+ * component hands in its state, setters and refs; no React hooks here.
+ */
+import type { Dispatch, MutableRefObject, SetStateAction } from "react";
+import { emptyActivityTrace } from "@/lib/agent-activity-trace";
+import {
+  natalRecastMeaning,
+  workingRectificationHouseTable,
+} from "@/lib/rectification-candidate-result";
+import {
+  rectificationAdoptingLabel,
+  isAbortError,
+} from "@/lib/rectification-surface-state";
+import type { CandidateResult } from "@/lib/rectification-chat-snapshot";
+import type {
+  RectificationRunOutcome,
+  RectificationSnapshotLoader,
+  RectificationTurnAction,
+  RectificationTurnContinuation,
+} from "@/lib/rectification-chat-turn-run";
+import type { RenderMessage } from "@/components/rectification-message-entry";
+
+export type RectificationCandidateAcceptDeps = Readonly<{
+  caseId: string;
+  sessionId: string;
+  busy: boolean;
+  readonly: boolean;
+  candidateResult: CandidateResult;
+  acceptingCandidateId: string | null;
+  keyCounter: MutableRefObject<number>;
+  runAbort: MutableRefObject<AbortController | null>;
+  lastRunOutcome: MutableRefObject<RectificationRunOutcome>;
+  conversationAnchor: Readonly<{ pinLatestTurn: () => void }>;
+  setError: Dispatch<SetStateAction<string>>;
+  setMessages: Dispatch<SetStateAction<RenderMessage[]>>;
+  setAcceptingCandidateId: Dispatch<SetStateAction<string | null>>;
+  setCandidateResult: Dispatch<SetStateAction<CandidateResult>>;
+  setSavedTime: Dispatch<SetStateAction<string | null>>;
+  setSavedStatus: Dispatch<SetStateAction<"accepted" | "confirmed" | null>>;
+  setPending: (value: boolean) => void;
+  beginLiveRun: (baseLabel: string) => void;
+  loadCaseSnapshot: RectificationSnapshotLoader;
+  send: (
+    action: RectificationTurnAction,
+    messageText: string,
+    continuation?: RectificationTurnContinuation,
+  ) => Promise<void>;
+  onCompleted?: () => void;
+  onSaved?: (time: string, status: "accepted" | "confirmed") => void;
+}>;
+
+export async function runRectificationCandidateAccept(
+  deps: RectificationCandidateAcceptDeps,
+  candidateId: string,
+): Promise<void> {
+  const {
+    caseId,
+    sessionId,
+    busy,
+    readonly,
+    candidateResult,
+    acceptingCandidateId,
+    keyCounter,
+    runAbort,
+    lastRunOutcome,
+    conversationAnchor,
+    setError,
+    setMessages,
+    setAcceptingCandidateId,
+    setCandidateResult,
+    setSavedTime,
+    setSavedStatus,
+    setPending,
+    beginLiveRun,
+    loadCaseSnapshot,
+    send,
+    onCompleted,
+    onSaved,
+  } = deps;
+  if (!candidateResult || acceptingCandidateId || busy || readonly) return;
+  setError("");
+  setAcceptingCandidateId(candidateId);
+  setPending(true);
+  // Adoption is a server round trip followed by an agent turn; the reader sees
+  // one live row for the whole of it instead of a greyed button.
+  const candidateTime = candidateResult.candidates.find((candidate) => candidate.candidateId === candidateId)?.time ?? "";
+  const adoptingLabel = rectificationAdoptingLabel(candidateTime);
+  keyCounter.current += 1;
+  const assistantRenderKey = `v9-adopt-assistant-${keyCounter.current}`;
+  beginLiveRun(adoptingLabel);
+  setMessages((current) => [
+    ...current,
+    {
+      role: "assistant",
+      text: "",
+      renderKey: assistantRenderKey,
+      state: "thinking",
+      activityTrace: emptyActivityTrace(),
+      activity: { phase: "evidence-validation", label: adoptingLabel, startedAt: Date.now() },
+    },
+  ]);
+  conversationAnchor.pinLatestTurn();
+  const abortController = new AbortController();
+  runAbort.current = abortController;
+  try {
+    const response = await fetch(
+      `/api/rectification/cases/${encodeURIComponent(caseId)}/candidates/accept`,
+      {
+        method: "POST",
+        headers: { "content-type": "application/json" },
+        signal: abortController.signal,
+        body: JSON.stringify({
+          sessionId,
+          resultId: candidateResult.resultId,
+          candidateId,
+          requestId: globalThis.crypto.randomUUID(),
+          mode: "range",
+        }),
+      },
+    );
+    const payload = await response.json().catch(() => null);
+    if (!response.ok || payload?.ok !== true || payload?.status !== "accepted") {
+      throw new Error(payload?.error || payload?.message || "暂时无法采用该候选时间");
+    }
+    setCandidateResult((current) => {
+      if (!current) return current;
+      const selectedTime = typeof payload.saved_time === "string" ? payload.saved_time.slice(0, 5) : current.selectedTime;
+      const next = {
+        ...current,
+        selectedTime,
+        selectionKind: "user_accepted" as const,
+      };
+      const houseTable = workingRectificationHouseTable(next);
+      const recastMeaning = natalRecastMeaning(houseTable);
+      return {
+        ...next,
+        houseTable: houseTable ?? current.houseTable,
+        natalRecast: houseTable && recastMeaning
+          ? {
+              time: houseTable.time,
+              lagna: houseTable.lagna,
+              user_meaning: recastMeaning,
+              unique_minute_claim: false as const,
+              confirmation_allowed: false as const,
+            }
+          : current.natalRecast,
+      };
+    });
+    setSavedTime(payload.saved_time);
+    setSavedStatus("accepted");
+    onSaved?.(payload.saved_time, "accepted");
+    onCompleted?.();
+    await loadCaseSnapshot();
+    await send("read_only", "", { reuseAssistantRenderKey: assistantRenderKey, label: adoptingLabel });
+  } catch (caught) {
+    if (isAbortError(caught)) {
+      lastRunOutcome.current = "stopped";
+      setMessages((current) => current.map((message) => (
+        message.renderKey !== assistantRenderKey ? message : {
+          ...message,
+          state: "settled" as const,
+          failed: false,
+          stopped: true,
+          activity: undefined,
+        }
+      )));
+      return;
+    }
+    lastRunOutcome.current = "failed";
+    setMessages((current) => current.filter((message) => message.renderKey !== assistantRenderKey));
+    setError(caught instanceof Error ? caught.message : "暂时无法采用该候选时间");
+  } finally {
+    if (runAbort.current === abortController) runAbort.current = null;
+    if (lastRunOutcome.current === null) lastRunOutcome.current = "succeeded";
+    setAcceptingCandidateId(null);
+    setPending(false);
+  }
+}
diff --git a/frontend/src/lib/rectification-chat-choice-run.ts b/frontend/src/lib/rectification-chat-choice-run.ts
new file mode 100644
index 00000000..4ad0ecb7
--- /dev/null
+++ b/frontend/src/lib/rectification-chat-choice-run.ts
@@ -0,0 +1,283 @@
+/**
+ * A tapped choice (answer, stop, skip this probe) from the rectification chat:
+ * the local answered mark and live row, the structured POST, the transcript
+ * merge after the Case re-read, the follow-up turn on the same row, and the
+ * roll-back when the tap did not land (BUG-1046). Moved out of
+ * RectificationAgenticChat's `submitStructuredChoice` unchanged
+ * (TASK-rectification-code-split-20260926). A parameter function: the
+ * component hands in its state, setters and refs; no React hooks here.
+ */
+import type { Dispatch, MutableRefObject, SetStateAction } from "react";
+import type { ChatMessage } from "@/lib/chat-message-view";
+import { emptyActivityTrace } from "@/lib/agent-activity-trace";
+import { RECTIFICATION_ACTIVITY_PROGRESS_LABELS } from "@/lib/rectification-activity-labels";
+import {
+  RECTIFICATION_CHOICE_SUBMIT_FAILED_COPY,
+  isAbortError,
+} from "@/lib/rectification-surface-state";
+import {
+  CHOICE_ACTION,
+  SKIP_PROBE_ACTION,
+  STOP_ACTION,
+  shouldContinueAfterStructuredChoice,
+  type ChoiceOptionId,
+} from "@/lib/rectification-agentic/v9/choice-action";
+import { isPersistedFocusId, type ChoiceKey, type RectificationChoiceCard as ChoiceCardModel } from "@/lib/rectification-agentic/v9/choice-card";
+import {
+  appendUnseenAssistantTurns,
+  applySnapshotTurnsToMessages,
+  mergeTurnQuestions,
+} from "@/lib/rectification-snapshot-messages";
+import {
+  markQuestionAnswered,
+  messagesFromTurns,
+  withdrawAnswerMark,
+  type PersistedTurn,
+} from "@/lib/rectification-chat-messages";
+import type { CurrentQuestionModel } from "@/lib/rectification-chat-snapshot";
+import type {
+  RectificationRunOutcome,
+  RectificationSnapshotLoader,
+  RectificationTurnAction,
+  RectificationTurnContinuation,
+} from "@/lib/rectification-chat-turn-run";
+import type { RenderMessage } from "@/components/rectification-message-entry";
+
+export type RectificationStructuredChoiceAction = typeof CHOICE_ACTION | typeof STOP_ACTION | typeof SKIP_PROBE_ACTION;
+export type RectificationStructuredChoiceOverride = Readonly<{
+  focusId?: string;
+  questionId?: string | null;
+  probeId?: string | null;
+  caseRevision?: number | null;
+}>;
+
+export type RectificationStructuredChoiceDeps = Readonly<{
+  caseId: string;
+  sessionId: string;
+  busy: boolean;
+  readonly: boolean;
+  choiceCard: ChoiceCardModel | null;
+  currentQuestion: CurrentQuestionModel | null;
+  keyCounter: MutableRefObject<number>;
+  runAbort: MutableRefObject<AbortController | null>;
+  lastRunOutcome: MutableRefObject<RectificationRunOutcome>;
+  conversationAnchor: Readonly<{ pinLatestTurn: () => void }>;
+  actionIdForChoice: (focusId: string, optionId: ChoiceOptionId) => string;
+  setError: Dispatch<SetStateAction<string>>;
+  setMessages: Dispatch<SetStateAction<RenderMessage[]>>;
+  setChoiceNonce: Dispatch<SetStateAction<number>>;
+  setNextUserActionId: Dispatch<SetStateAction<string | null>>;
+  setPending: (value: boolean) => void;
+  beginLiveRun: (baseLabel: string) => void;
+  loadCaseSnapshot: RectificationSnapshotLoader;
+  send: (
+    action: RectificationTurnAction,
+    messageText: string,
+    continuation?: RectificationTurnContinuation,
+  ) => Promise<void>;
+  onCompleted?: () => void;
+  onMessagesChange?: (messages: ChatMessage[]) => void;
+  onProfileIncomplete?: () => void;
+}>;
+
+export async function runRectificationStructuredChoice(
+  deps: RectificationStructuredChoiceDeps,
+  action: RectificationStructuredChoiceAction,
+  optionId: ChoiceKey | "stop" | "skip_probe",
+  override?: RectificationStructuredChoiceOverride,
+): Promise<void> {
+  const {
+    caseId,
+    sessionId,
+    busy,
+    readonly,
+    choiceCard,
+    currentQuestion,
+    keyCounter,
+    runAbort,
+    lastRunOutcome,
+    conversationAnchor,
+    actionIdForChoice,
+    setError,
+    setMessages,
+    setChoiceNonce,
+    setNextUserActionId,
+    setPending,
+    beginLiveRun,
+    loadCaseSnapshot,
+    send,
+    onCompleted,
+    onMessagesChange,
+    onProfileIncomplete,
+  } = deps;
+  const focusId = override?.focusId ?? choiceCard?.focus_id ?? (
+    action === STOP_ACTION && currentQuestion?.kind === "collect_spoken"
+      ? currentQuestion.focus_id
+      : null
+  );
+  if (busy || readonly) return;
+  if (action !== STOP_ACTION && (!focusId || (!override && !choiceCard))) return;
+  if (focusId && !isPersistedFocusId(focusId)) {
+    setError("当前选择题已失效，请等待下一问。");
+    return;
+  }
+  const questionId = override?.questionId ?? choiceCard?.question_id ?? currentQuestion?.question_id ?? null;
+  const probeId = override?.probeId ?? choiceCard?.probe_id;
+  const expectedRevision = override?.caseRevision ?? choiceCard?.case_revision ?? 0;
+  const actionId = actionIdForChoice(focusId ?? caseId, optionId);
+  setError("");
+  keyCounter.current += 1;
+  const turnKey = keyCounter.current;
+  const assistantRenderKey = `v9-choice-assistant-${turnKey}`;
+  const recordingLabel = RECTIFICATION_ACTIVITY_PROGRESS_LABELS.recording_answer;
+  beginLiveRun(recordingLabel);
+  setMessages((current) => [
+    ...markQuestionAnswered(current, focusId ?? "", optionId),
+    {
+      role: "assistant",
+      text: "",
+      renderKey: assistantRenderKey,
+      state: "thinking",
+      activityTrace: emptyActivityTrace(),
+      activity: {
+        phase: "evidence-validation",
+        label: recordingLabel,
+        startedAt: Date.now(),
+      },
+    },
+  ]);
+  conversationAnchor.pinLatestTurn();
+  setPending(true);
+  // BUG-1046 (D2): a tap that did not land takes back its local answered
+  // mark and placeholder; the card key changes (answer_option → nonce), so
+  // the card remounts clean and one tappable card is left.
+  const rollBackFailedChoice = () => {
+    setMessages((current) => withdrawAnswerMark(
+      current.filter((message) => message.renderKey !== assistantRenderKey),
+      focusId ?? "",
+      optionId,
+    ));
+    setChoiceNonce((current) => current + 1);
+  };
+  // The server may have moved on (stale_question, a dropped response after
+  // it applied): re-read the Case so the card reflects what it holds.
+  const reloadAfterFailedChoice = () => loadCaseSnapshot((turns) => {
+    setMessages((current) => applySnapshotTurnsToMessages(
+      current,
+      turns,
+      (incoming) => messagesFromTurns(incoming as readonly PersistedTurn[]),
+    ));
+  });
+  const abortController = new AbortController();
+  runAbort.current = abortController;
+  try {
+    const response = await fetch("/api/rectification/agent", {
+      method: "POST",
+      headers: { "content-type": "application/json" },
+      signal: abortController.signal,
+      body: JSON.stringify({
+        caseId,
+        sessionId,
+        requestId: actionId,
+        action,
+        actionId,
+        ...(focusId ? { focusId } : {}),
+        ...(questionId ? { questionId } : {}),
+        probeId: probeId ?? null,
+        optionId: optionId === "stop" ? undefined : optionId,
+        expectedRevision,
+        origin: "choice_click",
+        clientActionId: actionId,
+      }),
+    });
+    const payload = await response.json().catch(() => null);
+    if (!response.ok) {
+      rollBackFailedChoice();
+      if (payload?.code === "profile_incomplete") {
+        onProfileIncomplete?.();
+        return;
+      }
+      setError(RECTIFICATION_CHOICE_SUBMIT_FAILED_COPY);
+      await reloadAfterFailedChoice();
+      return;
+    }
+    const willContinue = shouldContinueAfterStructuredChoice(payload?.nextAction, payload);
+    const payloadNextActionId = typeof payload?.next_user_action?.id === "string"
+      ? payload.next_user_action.id.trim()
+      : "";
+    if (payloadNextActionId) setNextUserActionId(payloadNextActionId);
+    onCompleted?.();
+    await loadCaseSnapshot((turns) => {
+      if (willContinue) {
+        // D4 (BUG-1046, the same gap BUG-685 closed for the tie-break entry): a turn
+        // the server wrote while applying the tap joins the transcript,
+        // above the row the follow-up run continues on.
+        setMessages((current) => mergeTurnQuestions(
+          appendUnseenAssistantTurns(
+            current,
+            messagesFromTurns(turns as readonly PersistedTurn[]),
+            { beforeRenderKey: assistantRenderKey },
+          ),
+          turns,
+        ));
+        return;
+      }
+      const narration = typeof payload?.narration === "string" && payload.narration.trim()
+        ? payload.narration.trim()
+        : "已记录你的选择。";
+      setMessages((current) => {
+        const withoutPlaceholder = current.filter((message) => message.renderKey !== assistantRenderKey);
+        const withHistory = appendUnseenAssistantTurns(
+          mergeTurnQuestions(withoutPlaceholder, turns),
+          messagesFromTurns(turns as readonly PersistedTurn[]),
+        );
+        if (withHistory.length > withoutPlaceholder.length) return withHistory;
+        return [
+          ...withHistory,
+          {
+            role: "assistant" as const,
+            text: narration,
+            renderKey: assistantRenderKey,
+            state: "settled" as const,
+            activity: undefined,
+          },
+        ];
+      });
+    });
+    if (willContinue) {
+      // The follow-up turn continues on the row already in place: no removed
+      // row, no effect hop, and `busy` never drops in between (so the next
+      // card cannot flash before the turn hides it).
+      await send("read_only", "", { reuseAssistantRenderKey: assistantRenderKey, label: recordingLabel });
+    } else {
+      const narration = typeof payload?.narration === "string" && payload.narration.trim()
+        ? payload.narration.trim()
+        : "已记录你的选择。";
+      onMessagesChange?.([
+        { role: "assistant", text: narration },
+      ]);
+    }
+  } catch (caught) {
+    if (isAbortError(caught)) {
+      lastRunOutcome.current = "stopped";
+      setMessages((current) => current.map((message) => (
+        message.renderKey !== assistantRenderKey ? message : {
+          ...message,
+          state: "settled" as const,
+          failed: false,
+          stopped: true,
+          activity: undefined,
+        }
+      )));
+      return;
+    }
+    lastRunOutcome.current = "failed";
+    rollBackFailedChoice();
+    setError(RECTIFICATION_CHOICE_SUBMIT_FAILED_COPY);
+    await reloadAfterFailedChoice();
+  } finally {
+    if (runAbort.current === abortController) runAbort.current = null;
+    if (lastRunOutcome.current === null) lastRunOutcome.current = "succeeded";
+    setPending(false);
+  }
+}
diff --git a/frontend/src/lib/rectification-chat-message-actions.ts b/frontend/src/lib/rectification-chat-message-actions.ts
new file mode 100644
index 00000000..10ed0cb4
--- /dev/null
+++ b/frontend/src/lib/rectification-chat-message-actions.ts
@@ -0,0 +1,88 @@
+/**
+ * Per-message actions of the rectification chat: copy (question included) and
+ * regenerate the latest settled answer. Moved out of RectificationAgenticChat
+ * unchanged (TASK-rectification-code-split-20260926). Parameter functions;
+ * no React hooks here.
+ */
+import type { Dispatch, SetStateAction } from "react";
+import { copyTextForMessage } from "@/lib/rectification-agentic/v9/turn-question";
+import type { RenderMessage } from "@/components/rectification-message-entry";
+
+export type RectificationCopyMessageDeps = Readonly<{
+  setCopiedMessageKey: Dispatch<SetStateAction<string | null>>;
+}>;
+
+export async function copyRectificationMessage(
+  deps: RectificationCopyMessageDeps,
+  message: RenderMessage,
+): Promise<void> {
+  const { setCopiedMessageKey } = deps;
+  try {
+    await navigator.clipboard.writeText(copyTextForMessage(message.text, message.question));
+    setCopiedMessageKey(message.renderKey);
+    window.setTimeout(() => setCopiedMessageKey((current) => (
+      current === message.renderKey ? null : current
+    )), 1_500);
+  } catch {
+    // Clipboard permission failures must not interrupt the conversation.
+  }
+}
+
+export type RectificationRegenerateMessageDeps = Readonly<{
+  caseId: string;
+  sessionId: string;
+  busy: boolean;
+  readonly: boolean;
+  regeneratingMessageKey: string | null;
+  setError: Dispatch<SetStateAction<string>>;
+  setMessages: Dispatch<SetStateAction<RenderMessage[]>>;
+  setRegeneratingMessageKey: Dispatch<SetStateAction<string | null>>;
+}>;
+
+export async function regenerateRectificationMessage(
+  deps: RectificationRegenerateMessageDeps,
+  message: RenderMessage,
+): Promise<void> {
+  const {
+    caseId,
+    sessionId,
+    busy,
+    readonly,
+    regeneratingMessageKey,
+    setError,
+    setMessages,
+    setRegeneratingMessageKey,
+  } = deps;
+  if (!message.turnId || regeneratingMessageKey || busy || readonly) return;
+  setError("");
+  setRegeneratingMessageKey(message.renderKey);
+  const previousText = message.text;
+  try {
+    const response = await fetch(
+      `/api/rectification/cases/${encodeURIComponent(caseId)}/turns/${encodeURIComponent(message.turnId)}/regenerate`,
+      {
+        method: "POST",
+        headers: { "content-type": "application/json" },
+        body: JSON.stringify({
+          sessionId,
+          requestId: globalThis.crypto.randomUUID(),
+        }),
+      },
+    );
+    const payload = await response.json().catch(() => null);
+    if (!response.ok || payload?.ok !== true || typeof payload.assistantMessage !== "string") {
+      throw new Error(payload?.message || payload?.error || "暂时无法重新生成回答");
+    }
+    const nextText = payload.assistantMessage;
+    setMessages((current) => current.map((item) => item.renderKey === message.renderKey
+      ? { ...item, text: nextText, state: "settled" }
+      : item));
+  } catch (caught) {
+    setMessages((current) => current.map((item) => item.renderKey === message.renderKey
+      ? { ...item, text: previousText, state: "settled" }
+      : item));
+    setError(caught instanceof Error ? caught.message : "暂时无法重新生成回答");
+  } finally {
+    setRegeneratingMessageKey((current) => current === message.renderKey ? null : current);
+  }
+}
diff --git a/frontend/src/lib/rectification-chat-messages.ts b/frontend/src/lib/rectification-chat-messages.ts
new file mode 100644
index 00000000..23cf81f4
--- /dev/null
+++ b/frontend/src/lib/rectification-chat-messages.ts
@@ -0,0 +1,163 @@
+/**
+ * Pure transcript helpers of the rectification chat surface: persisted turns
+ * to render messages, the local "answered" mark on a question and its undo,
+ * and the persisted receipt view. Moved out of rectification-agentic-chat.tsx
+ * unchanged (TASK-rectification-code-split-20260926); no React hooks here.
+ */
+import { activityTraceFromReceipt } from "@/lib/rectification-activity-labels";
+import {
+  createRectificationActivityReceiptState,
+  receiptFromRectificationActivityState,
+  reduceRectificationActivityReceipt,
+  type CompletedActivityReceiptView,
+} from "@/lib/rectification-activity-receipt";
+import {
+  isPublicRectificationMethod,
+  isPublicRectificationTool,
+} from "@/lib/rectification-agentic/v9/public-receipt";
+import { isIncompleteRunBanner } from "@/lib/rectification-agentic/v9/run-diagnostic";
+import { isStructuredChoiceUserText } from "@/lib/rectification-agentic/v9/choice-action";
+import type { ChoiceKey } from "@/lib/rectification-agentic/v9/choice-card";
+import { parseTurnQuestion, questionIsAnswered } from "@/lib/rectification-agentic/v9/turn-question";
+import type { RenderMessage } from "@/components/rectification-message-entry";
+
+export type PersistedTurn = Readonly<{
+  id: string;
+  role: "user" | "assistant";
+  text: string | null;
+  status: string;
+  question?: unknown;
+  offer_result_id?: string | null;
+  receipt?: Readonly<{
+    status: string;
+    phases: readonly string[];
+    tool_activities?: readonly Readonly<{
+      tool: string;
+      status: string;
+      methods?: readonly string[];
+      started_at?: string | null;
+      elapsed_ms?: number | null;
+      detail?: Readonly<Record<string, unknown>> | null;
+    }>[];
+    tools: readonly string[];
+    methods?: readonly string[];
+    skill_name?: string;
+    skill_version?: string;
+  }> | null;
+}>;
+
+export function markQuestionAnswered(
+  current: RenderMessage[],
+  focusId: string,
+  selected: ChoiceKey | "stop" | "skip_probe" | "typed",
+): RenderMessage[] {
+  return current.map((message) => {
+    const question = message.question;
+    if (!question || question.focus_id !== focusId || questionIsAnswered(question)) return message;
+    return {
+      ...message,
+      question: {
+        ...question,
+        status: "resolved",
+        answer_option: selected === "typed" ? null : selected,
+      },
+    };
+  });
+}
+
+/**
+ * BUG-1046: undo `markQuestionAnswered` when the answer never reached the
+ * server, so the question is active again with no option picked. Only the mark
+ * this action made is undone; a server-resolved question is left alone.
+ */
+export function withdrawAnswerMark(
+  current: RenderMessage[],
+  focusId: string,
+  selected: ChoiceKey | "stop" | "skip_probe" | "typed",
+): RenderMessage[] {
+  const marked = selected === "typed" ? null : selected;
+  return current.map((message) => {
+    const question = message.question;
+    if (!question || question.focus_id !== focusId) return message;
+    if (question.status !== "resolved" || question.answer_option !== marked) return message;
+    return { ...message, question: { ...question, status: "active", answer_option: null } };
+  });
+}
+
+export function isSettledAssistantMessage(message: RenderMessage): boolean {
+  return message.role === "assistant" && message.state === "settled" && !message.failed;
+}
+
+export function snapshotTurns(payload: { turns?: unknown } | null | undefined): readonly unknown[] {
+  return Array.isArray(payload?.turns) ? payload.turns : [];
+}
+
+export function completedReceiptFromPersisted(receipt: PersistedTurn["receipt"]): CompletedActivityReceiptView {
+  if (!receipt) return { steps: [], methods: [] };
+  if (Array.isArray(receipt.tool_activities)) {
+    let state = createRectificationActivityReceiptState();
+    for (const activity of receipt.tool_activities) {
+      if (!isPublicRectificationTool(activity.tool)
+        || (activity.status !== "completed" && activity.status !== "failed")) continue;
+      state = reduceRectificationActivityReceipt(state, {
+        tool: activity.tool,
+        status: activity.status,
+        methods: activity.status === "completed" && Array.isArray(activity.methods)
+          ? activity.methods.filter(isPublicRectificationMethod)
+          : [],
+      });
+    }
+    return receiptFromRectificationActivityState(state);
+  }
+  return {
+    steps: [...new Set((receipt.tools ?? []).filter(isPublicRectificationTool))],
+    methods: [...new Set((receipt.methods ?? []).filter(isPublicRectificationMethod))],
+  };
+}
+
+export function hasActivityReceipt(receipt: CompletedActivityReceiptView): boolean {
+  return receipt.steps.length > 0 || receipt.methods.length > 0 || Boolean(receipt.failedTool);
+}
+
+export function persistedTurnFailed(turn: PersistedTurn): boolean {
+  return turn.status === "failed"
+    || turn.status === "retryable"
+    || turn.receipt?.status === "failed"
+    || turn.receipt?.status === "degraded"
+    || turn.receipt?.status === "blocked";
+}
+
+export function messagesFromTurns(initialTurns: readonly PersistedTurn[]): RenderMessage[] {
+  return initialTurns.flatMap((turn, index): RenderMessage[] => {
+    const key = `persisted-${turn.id}-${index}`;
+    if (turn.role === "assistant") {
+      const failed = persistedTurnFailed(turn);
+      const raw = failed ? "" : turn.text ?? "";
+      if (failed && !raw) return [];
+      if (isIncompleteRunBanner(raw)) return [];
+      const completedReceipt = completedReceiptFromPersisted(turn.receipt);
+      return [{
+        role: "assistant",
+        text: raw,
+        renderKey: key,
+        state: turn.status === "completed" || failed ? "settled" : "thinking",
+        completedReceipt,
+        activityTrace: activityTraceFromReceipt(completedReceipt),
+        failed,
+        turnId: turn.id,
+        question: parseTurnQuestion(turn.question) ?? undefined,
+        candidateOffer: typeof turn.offer_result_id === "string"
+          ? { resultId: turn.offer_result_id }
+          : undefined,
+      }];
+    }
+    if (isIncompleteRunBanner(turn.text ?? "")) return [];
+    if (isStructuredChoiceUserText(turn.text)) return [];
+    return [{
+      role: "user",
+      text: turn.text ?? "",
+      renderKey: key,
+      state: "settled",
+    }];
+  });
+}
diff --git a/frontend/src/lib/rectification-chat-question-repair.ts b/frontend/src/lib/rectification-chat-question-repair.ts
new file mode 100644
index 00000000..14b13e4e
--- /dev/null
+++ b/frontend/src/lib/rectification-chat-question-repair.ts
@@ -0,0 +1,99 @@
+/**
+ * Question recovery of the rectification chat: re-read the Case while the
+ * next question is `preparing`, and the one-button repair when it is
+ * `unavailable`. Moved out of RectificationAgenticChat unchanged
+ * (TASK-rectification-code-split-20260926). Parameter functions; the timer
+ * itself stays in the component (useVisibilityAwarePoll). No React hooks here.
+ */
+import { startTransition, type Dispatch, type SetStateAction } from "react";
+import {
+  RECTIFICATION_QUESTION_REPAIR_LIMIT,
+  type RectificationCaseSnapshotPayload,
+} from "@/lib/rectification-surface-state";
+import { parseRectificationChoiceCard } from "@/lib/rectification-agentic/v9/choice-card";
+import { applySnapshotTurnsToMessages } from "@/lib/rectification-snapshot-messages";
+import { messagesFromTurns, type PersistedTurn } from "@/lib/rectification-chat-messages";
+import { currentQuestionFromSnapshot } from "@/lib/rectification-chat-snapshot";
+import type { RectificationSnapshotLoader } from "@/lib/rectification-chat-turn-run";
+import type { RenderMessage } from "@/components/rectification-message-entry";
+
+export type RectificationQuestionRefetchDeps = Readonly<{
+  loadCaseSnapshot: RectificationSnapshotLoader;
+  setMessages: Dispatch<SetStateAction<RenderMessage[]>>;
+}>;
+
+export async function refetchRectificationQuestion(deps: RectificationQuestionRefetchDeps): Promise<void> {
+  const { loadCaseSnapshot, setMessages } = deps;
+  await loadCaseSnapshot((turns) => {
+    setMessages((current) => applySnapshotTurnsToMessages(
+      current,
+      turns,
+      (incoming) => messagesFromTurns(incoming as readonly PersistedTurn[]),
+    ));
+  });
+}
+
+export type RectificationQuestionRepairDeps = Readonly<{
+  caseId: string;
+  sessionId: string;
+  questionRepairing: boolean;
+  questionRepairAttempts: number;
+  setQuestionRepairing: Dispatch<SetStateAction<boolean>>;
+  setQuestionRepairAttempts: Dispatch<SetStateAction<number>>;
+  applyCaseSnapshot: (payload: RectificationCaseSnapshotPayload | null) => void;
+  loadCaseSnapshot: RectificationSnapshotLoader;
+  setMessages: Dispatch<SetStateAction<RenderMessage[]>>;
+}>;
+
+export async function repairRectificationQuestion(deps: RectificationQuestionRepairDeps): Promise<void> {
+  const {
+    caseId,
+    sessionId,
+    questionRepairing,
+    questionRepairAttempts,
+    setQuestionRepairing,
+    setQuestionRepairAttempts,
+    applyCaseSnapshot,
+    loadCaseSnapshot,
+    setMessages,
+  } = deps;
+  if (questionRepairing || questionRepairAttempts >= RECTIFICATION_QUESTION_REPAIR_LIMIT) return;
+  setQuestionRepairing(true);
+  try {
+    const response = await fetch(
+      `/api/rectification/cases/${encodeURIComponent(caseId)}/repair-exit`,
+      {
+        method: "POST",
+        headers: { "content-type": "application/json" },
+        cache: "no-store",
+        body: JSON.stringify({ sessionId }),
+      },
+    );
+    const payload = await response.json().catch(() => null);
+    if (response.ok && payload) {
+      startTransition(() => {
+        applyCaseSnapshot(payload);
+      });
+      const recovered = Boolean(
+        currentQuestionFromSnapshot(payload.current_question)
+        || parseRectificationChoiceCard(payload.choice_card)
+        || payload.case?.accepted_time
+        || payload.case?.confirmed_time
+      );
+      if (!recovered) setQuestionRepairAttempts((current) => current + 1);
+    } else {
+      await loadCaseSnapshot((turns) => {
+        setMessages((current) => applySnapshotTurnsToMessages(
+          current,
+          turns,
+          (incoming) => messagesFromTurns(incoming as readonly PersistedTurn[]),
+        ));
+      });
+      setQuestionRepairAttempts((current) => current + 1);
+    }
+  } catch {
+    setQuestionRepairAttempts((current) => current + 1);
+  } finally {
+    setQuestionRepairing(false);
+  }
+}
diff --git a/frontend/src/lib/rectification-chat-snapshot.ts b/frontend/src/lib/rectification-chat-snapshot.ts
new file mode 100644
index 00000000..bb3f3cf7
--- /dev/null
+++ b/frontend/src/lib/rectification-chat-snapshot.ts
@@ -0,0 +1,94 @@
+/**
+ * Pure reads of the Case snapshot payload for the rectification chat surface:
+ * the current question, its source, and the initial state that arrives with
+ * the reveal. Moved out of rectification-agentic-chat.tsx unchanged
+ * (TASK-rectification-code-split-20260926); no React hooks here.
+ */
+import {
+  parseRectificationCandidateResult,
+  type RectificationCandidateResult,
+} from "@/lib/rectification-candidate-result";
+import {
+  searchWindowFromSnapshot,
+  caseStageFromSnapshot,
+  interviewStopReasonFromSnapshot,
+  interviewSessionOutcomeFromSnapshot,
+  birthTimeSourceFromSnapshot,
+  type RectificationCaseSnapshotPayload,
+} from "@/lib/rectification-surface-state";
+import type { RectificationTimelineStage } from "@/lib/rectification-timeline-scale";
+import { isRectificationCaseStatus, type RectificationCaseStatus } from "@/lib/rectification-agentic/v9/case-status";
+import { parseRectificationChoiceCard, type RectificationChoiceCard as ChoiceCardModel } from "@/lib/rectification-agentic/v9/choice-card";
+
+export type CandidateResult = RectificationCandidateResult | null;
+export type CurrentQuestionModel = Readonly<{
+  kind: "choice" | "collect_spoken";
+  prompt: string | null;
+  focus_id: string | null;
+  question_id: string | null;
+}>;
+
+export function currentQuestionFromSnapshot(value: unknown): CurrentQuestionModel | null {
+  if (!value || typeof value !== "object" || Array.isArray(value)) return null;
+  const question = value as { kind?: unknown; prompt?: unknown; focus_id?: unknown; question_id?: unknown };
+  if (question.kind !== "choice" && question.kind !== "collect_spoken" && question.kind !== "reverse_verify") {
+    return null;
+  }
+  return {
+    kind: question.kind === "collect_spoken" ? "collect_spoken" : "choice",
+    prompt: typeof question.prompt === "string" && question.prompt.trim()
+      ? question.prompt.trim()
+      : null,
+    focus_id: typeof question.focus_id === "string" ? question.focus_id : null,
+    question_id: typeof question.question_id === "string" ? question.question_id : null,
+  };
+}
+
+export function questionSourceFromSnapshot(value: unknown): "focus" | "unavailable" | null {
+  if (value === "unavailable") return "unavailable";
+  if (value === "focus") return "focus";
+  return null;
+}
+
+export type CaseSnapshotState = Readonly<{
+  candidate: CandidateResult;
+  question: CurrentQuestionModel | null;
+  questionSource: "focus" | "unavailable" | null;
+  choice: ChoiceCardModel | null;
+  caseStatus: RectificationCaseStatus | null;
+  savedTime: string | null;
+  savedStatus: "accepted" | "confirmed" | null;
+  nextUserActionId: string | null;
+  searchWindow: readonly [string, string] | null;
+  stage: RectificationTimelineStage | null;
+  interviewStopReason: string | null;
+  interviewSessionOutcome: string | null;
+  birthTimeSource: ReturnType<typeof birthTimeSourceFromSnapshot>;
+}>;
+
+export function nextUserActionIdFromSnapshot(payload: RectificationCaseSnapshotPayload | null): string | null {
+  const id = payload?.next_user_action?.id;
+  return typeof id === "string" && id.trim() ? id.trim() : null;
+}
+
+/** The snapshot that arrived with the reveal, as initial state; nothing is fetched on mount. */
+export function caseSnapshotState(payload: RectificationCaseSnapshotPayload | null): CaseSnapshotState | null {
+  if (!payload) return null;
+  const confirmedTime = typeof payload.case?.confirmed_time === "string" ? payload.case.confirmed_time : null;
+  const acceptedTime = typeof payload.case?.accepted_time === "string" ? payload.case.accepted_time : null;
+  return {
+    candidate: parseRectificationCandidateResult(payload.latest_result),
+    question: currentQuestionFromSnapshot(payload.current_question),
+    questionSource: questionSourceFromSnapshot(payload.question_source),
+    choice: parseRectificationChoiceCard(payload.choice_card),
+    caseStatus: isRectificationCaseStatus(payload.case?.status) ? payload.case.status : null,
+    savedTime: confirmedTime ?? acceptedTime,
+    savedStatus: confirmedTime ? "confirmed" : acceptedTime ? "accepted" : null,
+    nextUserActionId: nextUserActionIdFromSnapshot(payload),
+    searchWindow: searchWindowFromSnapshot(payload.case?.candidate_range),
+    stage: caseStageFromSnapshot(payload.case?.stage),
+    interviewStopReason: interviewStopReasonFromSnapshot(payload),
+    interviewSessionOutcome: interviewSessionOutcomeFromSnapshot(payload),
+    birthTimeSource: birthTimeSourceFromSnapshot(payload),
+  };
+}
diff --git a/frontend/src/lib/rectification-chat-turn-run.ts b/frontend/src/lib/rectification-chat-turn-run.ts
new file mode 100644
index 00000000..ad475b52
--- /dev/null
+++ b/frontend/src/lib/rectification-chat-turn-run.ts
@@ -0,0 +1,510 @@
+/**
+ * One rectification agent turn from the browser: the POST to
+ * /api/rectification/agent, the NDJSON stream read into the live row, the
+ * settle / fail / stop branches, and the snapshot re-read after the turn.
+ * Moved out of RectificationAgenticChat's `send` unchanged
+ * (TASK-rectification-code-split-20260926). A parameter function: the
+ * component hands in its state, setters and refs; no React hooks here.
+ */
+import type { Dispatch, MutableRefObject, SetStateAction } from "react";
+import { parseAgentReply } from "@/lib/agent-reply";
+import { nextActivityView, type AgentActivityView, type ChatMessage } from "@/lib/chat-message-view";
+import { createStreamFrameBuffer } from "@/lib/stream-frame-buffer";
+import {
+  completeActivityTrace,
+  completeActivityTraceStep,
+  emptyActivityTrace,
+  freezeLiveThink,
+  startActivityTraceStep,
+  type AgentActivityTraceItem,
+} from "@/lib/agent-activity-trace";
+import {
+  RECTIFICATION_ACTIVITY_PROGRESS_LABELS,
+  RECTIFICATION_ANALYZING_LIVE_LABEL,
+  RECTIFICATION_TOOL_DONE_LABELS,
+  RECTIFICATION_TOOL_PROGRESS_LABELS,
+  RECTIFICATION_TURN_PROGRESS_LABELS,
+  rectificationCompletedTrail,
+  rectificationToolActivityPhase,
+  rectificationTurnProgressPhase,
+} from "@/lib/rectification-activity-labels";
+import { isRectificationTurnProgressStage } from "@/lib/rectification-agentic/v9/turn-progress";
+import { withLiveStepLabel } from "@/lib/rectification-timeline-adapter";
+import {
+  createRectificationActivityReceiptState,
+  receiptFromRectificationActivityState,
+  reduceRectificationActivityReceipt,
+} from "@/lib/rectification-activity-receipt";
+import {
+  RECTIFICATION_INSUFFICIENT_CREDITS_NOTICE,
+  isAbortError,
+  rectificationInitialLiveLabel,
+} from "@/lib/rectification-surface-state";
+import {
+  isPublicRectificationActivity,
+  isPublicRectificationMethod,
+  isPublicRectificationTool,
+} from "@/lib/rectification-agentic/v9/public-receipt";
+import { userFacingRunFailure } from "@/lib/rectification-agentic/v9/run-diagnostic";
+import {
+  applySnapshotTurnsToMessages,
+  mergeTurnQuestions,
+} from "@/lib/rectification-snapshot-messages";
+import {
+  hasActivityReceipt,
+  markQuestionAnswered,
+  messagesFromTurns,
+  withdrawAnswerMark,
+  type PersistedTurn,
+} from "@/lib/rectification-chat-messages";
+import type { CurrentQuestionModel } from "@/lib/rectification-chat-snapshot";
+import type { RenderMessage } from "@/components/rectification-message-entry";
+
+export type RectificationTurnAction = "opening" | "message" | "read_only";
+export type RectificationTurnContinuation = Readonly<{ reuseAssistantRenderKey: string; label: string }>;
+export type RectificationRunOutcome = "succeeded" | "stopped" | "failed" | "readonly" | null;
+export type RectificationSnapshotLoader = (
+  mergeMessages?: (turns: readonly unknown[]) => void,
+) => Promise<unknown>;
+
+export type RectificationChatTurnDeps = Readonly<{
+  caseId: string;
+  sessionId: string;
+  selectedModelId: string;
+  busy: boolean;
+  readonly: boolean;
+  conversationReadonly: boolean;
+  keyCounter: MutableRefObject<number>;
+  currentQuestionRef: MutableRefObject<CurrentQuestionModel | null>;
+  runAbort: MutableRefObject<AbortController | null>;
+  lastRunOutcome: MutableRefObject<RectificationRunOutcome>;
+  conversationAnchor: Readonly<{ pinLatestTurn: () => void }>;
+  setError: Dispatch<SetStateAction<string>>;
+  setMessages: Dispatch<SetStateAction<RenderMessage[]>>;
+  setPending: (value: boolean) => void;
+  beginLiveRun: (baseLabel: string) => void;
+  rememberLiveActivity: (baseLabel: string, tool?: string | null) => string;
+  loadCaseSnapshot: RectificationSnapshotLoader;
+  onCompleted?: () => void;
+  onMessagesChange?: (messages: ChatMessage[]) => void;
+  onOpenBilling?: (options?: { source?: string }) => void;
+  onProfileIncomplete?: () => void;
+}>;
+
+/**
+ * Run one agent turn. A `continuation` reuses the live row an earlier step
+ * (a tapped choice, an adopted candidate) already put at the end of the
+ * transcript, so the reader sees one uninterrupted working row from the tap
+ * to the next question instead of a gap and a re-appended row. The caller
+ * of a continuation already holds `busy`.
+ */
+export async function runRectificationChatTurn(
+  deps: RectificationChatTurnDeps,
+  action: RectificationTurnAction,
+  messageText: string,
+  continuation?: RectificationTurnContinuation,
+): Promise<void> {
+  const {
+    caseId,
+    sessionId,
+    selectedModelId,
+    busy,
+    readonly,
+    conversationReadonly,
+    keyCounter,
+    currentQuestionRef,
+    runAbort,
+    lastRunOutcome,
+    conversationAnchor,
+    setError,
+    setMessages,
+    setPending,
+    beginLiveRun,
+    rememberLiveActivity,
+    loadCaseSnapshot,
+    onCompleted,
+    onMessagesChange,
+    onOpenBilling,
+    onProfileIncomplete,
+  } = deps;
+  const trimmed = action === "message" ? messageText.trim() : "";
+  if ((action === "message" && !trimmed) || conversationReadonly) return;
+  if (!continuation && busy) return;
+  setError("");
+  setPending(true);
+  const initialLabel = rectificationInitialLiveLabel(action, continuation?.label);
+  beginLiveRun(initialLabel);
+
+  keyCounter.current += 1;
+  const requestId = globalThis.crypto.randomUUID();
+  const turnKey = keyCounter.current;
+  const userRenderKey = `v9-user-${turnKey}`;
+  const assistantRenderKey = continuation?.reuseAssistantRenderKey ?? `v9-assistant-${turnKey}`;
+
+  const pendingFocusId = currentQuestionRef.current?.focus_id;
+  const liveRow: RenderMessage = {
+    role: "assistant",
+    text: "",
+    renderKey: assistantRenderKey,
+    state: "thinking",
+    activityTrace: emptyActivityTrace(),
+    activity: { phase: "evidence-validation", label: initialLabel, startedAt: Date.now() },
+  };
+  setMessages((current) => (continuation
+    ? current.map((message) => (message.renderKey === assistantRenderKey ? { ...liveRow, activity: message.activity ?? liveRow.activity } : message))
+    : [
+      ...(action === "message" && pendingFocusId
+        ? markQuestionAnswered(current, pendingFocusId, "typed")
+        : current),
+      ...(action === "message"
+        ? [{ role: "user", text: trimmed, renderKey: userRenderKey, state: "settled" } satisfies RenderMessage]
+        : []),
+      liveRow,
+    ]));
+  if (!continuation) conversationAnchor.pinLatestTurn();
+  // The typed answer never reached the server: the question it marked is
+  // still the pending one (BUG-1046, same as a failed tap).
+  const withdrawTypedMark = (current: RenderMessage[]) => (
+    !continuation && action === "message" && pendingFocusId
+      ? withdrawAnswerMark(current, pendingFocusId, "typed")
+      : current
+  );
+  let raw = "";
+  let runOutcome: "succeeded" | "stopped" | "failed" = "failed";
+  let activityTrace: readonly AgentActivityTraceItem[] = emptyActivityTrace();
+  let activityReceiptState = createRectificationActivityReceiptState();
+  let completedReceipt = receiptFromRectificationActivityState(activityReceiptState);
+  let completedTurnId: string | undefined;
+  let currentActivity: AgentActivityView | undefined = {
+    phase: "evidence-validation",
+    label: initialLabel,
+    startedAt: Date.now(),
+  };
+  // Every stream event lands in `frames`; it commits at most once per animation
+  // frame and releases text at a steady pace. The loop below never calls
+  // setMessages for a live turn directly except on `attempt.reset`.
+  const frames = createStreamFrameBuffer<null>({
+    initialMeta: null,
+    flush: (frame) => {
+      const text = frame.answer;
+      setMessages((current) => current.map((message) => message.renderKey === assistantRenderKey
+        ? {
+          ...message,
+          text,
+          activityTrace,
+          completedReceipt,
+          state: text.trim() ? "streaming" : "thinking",
+          activity: currentActivity,
+        }
+        : message));
+    },
+  });
+  const abortController = new AbortController();
+  runAbort.current = abortController;
+  try {
+    const response = await fetch("/api/rectification/agent", {
+      method: "POST",
+      headers: { "content-type": "application/json" },
+      signal: abortController.signal,
+      body: JSON.stringify({
+        caseId,
+        sessionId,
+        requestId,
+        action,
+        modelId: selectedModelId,
+        ...(action === "message" ? { message: trimmed } : {}),
+        origin: action === "read_only" ? "choice_click" : "typed",
+        clientActionId: requestId,
+      }),
+    });
+    // A turn the server turned down: the old non-2xx response, or the same
+    // facts as a `turn.rejected` event once the stream is already open
+    // (BUG-1047). Either way the live row goes and the typed mark returns.
+    const rejectTurn = (
+      response: { status: number },
+      payload: { code?: unknown; message?: unknown; error?: unknown } | null,
+    ) => {
+      const message = (typeof payload?.message === "string" && payload.message)
+        || (typeof payload?.error === "string" && payload.error)
+        || `请求失败（${response.status}）`;
+      setMessages((current) => withdrawTypedMark(
+        current.filter((message) => message.renderKey !== assistantRenderKey),
+      ));
+      if (payload?.code === "profile_incomplete") {
+        onProfileIncomplete?.();
+        return;
+      }
+      if (response.status === 402) {
+        // Keep the conversation on this page; the settings pane covers billing.
+        setError(RECTIFICATION_INSUFFICIENT_CREDITS_NOTICE);
+        onOpenBilling?.({ source: "rectification" });
+        return;
+      }
+      if (response.status === 401) setError("请先登录。");
+      else setError(message);
+    };
+    if (!response.ok) {
+      const payload = await response.json().catch(() => null);
+      rejectTurn(response, payload);
+      return;
+    }
+    if (!response.body) {
+      setMessages((current) => withdrawTypedMark(
+        current.filter((message) => message.renderKey !== assistantRenderKey),
+      ));
+      setError("服务暂时不可用，请稍后再试。");
+      return;
+    }
+
+    const reader = response.body.getReader();
+    const decoder = new TextDecoder();
+    let buffer = "";
+    let completed = false;
+    let streamFailed = false;
+    let runFailedMessage = "";
+    let rejected: { status: number; payload: { code?: unknown; message?: unknown } } | null = null;
+    // Stage line of a typed answer (BUG-1047 D3); null until the first
+    // `turn.progress`. It replaces the generic tool / "正在分析…" labels.
+    let stageLabel: string | null = null;
+    while (!rejected) {
+      const { done, value } = await reader.read();
+      if (done) break;
+      buffer += decoder.decode(value, { stream: true });
+      const lines = buffer.split("\n");
+      buffer = lines.pop() ?? "";
+      for (const line of lines) {
+        if (!line.trim()) continue;
+        let event: {
+          type?: unknown;
+          status?: unknown;
+          text?: unknown;
+          replace?: unknown;
+          message?: unknown;
+          tool?: unknown;
+          methods?: unknown;
+          turnId?: unknown;
+          code?: unknown;
+          activity?: unknown;
+          stage?: unknown;
+          httpStatus?: unknown;
+        };
+        try {
+          event = JSON.parse(line) as typeof event;
+        } catch {
+          continue;
+        }
+        if (typeof event.type !== "string") continue;
+        if (event.type === "turn.rejected" && typeof event.httpStatus === "number") {
+          rejected = { status: event.httpStatus, payload: { code: event.code, message: event.message } };
+          break;
+        }
+        if (event.type === "turn.progress" && isRectificationTurnProgressStage(event.stage)) {
+          stageLabel = RECTIFICATION_TURN_PROGRESS_LABELS[event.stage];
+          activityTrace = withLiveStepLabel(activityTrace, stageLabel);
+          currentActivity = nextActivityView(currentActivity, {
+            phase: rectificationTurnProgressPhase(event.stage),
+            label: rememberLiveActivity(stageLabel, null),
+          });
+          frames.touch();
+        } else if (event.type === "answer.delta" && typeof event.text === "string") {
+          raw = event.replace === true ? event.text : raw + event.text;
+          activityTrace = freezeLiveThink(activityTrace);
+          currentActivity = nextActivityView(currentActivity, {
+            phase: "answer-composition",
+            label: rememberLiveActivity("正在组织回答…"),
+          });
+          frames.setAnswer(raw);
+        } else if (event.type === "activity.changed" && isPublicRectificationActivity(event.activity)) {
+          const activity = event.activity;
+          currentActivity = nextActivityView(currentActivity, {
+            phase: "evidence-validation",
+            label: rememberLiveActivity(stageLabel ?? RECTIFICATION_ACTIVITY_PROGRESS_LABELS[activity]),
+          });
+          frames.touch();
+        } else if (event.type === "attempt.reset") {
+          raw = "";
+          activityTrace = emptyActivityTrace();
+          activityReceiptState = createRectificationActivityReceiptState();
+          completedReceipt = receiptFromRectificationActivityState(activityReceiptState);
+          completedTurnId = undefined;
+          if (stageLabel) stageLabel = RECTIFICATION_TURN_PROGRESS_LABELS.received;
+          currentActivity = nextActivityView(undefined, {
+            phase: "evidence-validation",
+            label: rememberLiveActivity(stageLabel ?? "正在处理…", null),
+          });
+          frames.reset();
+          setMessages((current) => current.map((message) => message.renderKey === assistantRenderKey
+            ? {
+              ...message,
+              text: "",
+              thinkingText: undefined,
+              activityTrace,
+              state: "thinking",
+              completedReceipt: undefined,
+              failed: false,
+              turnId: undefined,
+              activity: currentActivity,
+            }
+            : message));
+        } else if (event.type === "run.failed") {
+          streamFailed = true;
+          runFailedMessage = typeof event.message === "string" && event.message.trim()
+            ? event.message
+            : userFacingRunFailure(typeof event.code === "string" ? event.code : null);
+        } else if (event.type === "error") {
+          streamFailed = true;
+          setError(typeof event.message === "string" ? event.message : "生时校正暂时不可用，请稍后再试。");
+        } else if (event.type === "run.completed") {
+          completed = true;
+          if (typeof event.turnId === "string") completedTurnId = event.turnId;
+        } else if (event.type === "tool.activity") {
+          const tool = isPublicRectificationTool(event.tool) ? event.tool : null;
+          if (!tool) continue;
+          if (event.status === "started") {
+            activityTrace = startActivityTraceStep(
+              activityTrace,
+              tool,
+              stageLabel ?? RECTIFICATION_TOOL_PROGRESS_LABELS[tool],
+            );
+            currentActivity = nextActivityView(currentActivity, {
+              phase: rectificationToolActivityPhase(tool),
+              label: rememberLiveActivity(stageLabel ?? RECTIFICATION_TOOL_PROGRESS_LABELS[tool], tool),
+              completedTrail: rectificationCompletedTrail(activityReceiptState.completedSteps),
+            });
+            frames.touch();
+            continue;
+          }
+          if (event.status !== "completed" && event.status !== "failed") continue;
+          activityTrace = completeActivityTraceStep(
+            activityTrace,
+            tool,
+            RECTIFICATION_TOOL_DONE_LABELS[tool],
+          );
+          activityReceiptState = reduceRectificationActivityReceipt(activityReceiptState, {
+            tool,
+            status: event.status,
+            methods: event.status === "completed" && Array.isArray(event.methods)
+              ? event.methods.filter(isPublicRectificationMethod)
+              : [],
+          });
+          completedReceipt = receiptFromRectificationActivityState(activityReceiptState);
+          currentActivity = nextActivityView(currentActivity, {
+            phase: "evidence-validation",
+            label: stageLabel
+              ? rememberLiveActivity(stageLabel, null)
+              : rememberLiveActivity(RECTIFICATION_ANALYZING_LIVE_LABEL, null),
+            completedTrail: rectificationCompletedTrail(activityReceiptState.completedSteps),
+          });
+          frames.touch();
+        }
+      }
+    }
+    frames.settle();
+    if (rejected) {
+      await reader.cancel().catch(() => undefined);
+      rejectTurn({ status: rejected.status }, rejected.payload);
+      return;
+    }
+
+    const parsed = completed && !streamFailed ? parseAgentReply(raw) : { text: "", title: undefined };
+    const succeeded = completed && !streamFailed && Boolean(parsed.text);
+    setMessages((current) => current.flatMap((message): RenderMessage[] => {
+      if (message.renderKey !== assistantRenderKey) return [message];
+      if (succeeded) {
+        return [{
+          ...message,
+          text: parsed.text,
+          activityTrace: completeActivityTrace(activityTrace),
+          state: "settled",
+          completedReceipt,
+          failed: false,
+          turnId: completedTurnId,
+          activity: undefined,
+        }];
+      }
+      if (streamFailed || hasActivityReceipt(completedReceipt) || raw.trim()) {
+        return [{
+          ...message,
+          text: raw,
+          activityTrace: completeActivityTrace(activityTrace),
+          state: "settled",
+          completedReceipt,
+          failed: true,
+          activity: undefined,
+        }];
+      }
+      return [];
+    }));
+    if (!succeeded && raw.trim()) {
+      setError((current) => current || "回答未完成，已保留现有内容；本次不会扣点。");
+    } else if (!succeeded && runFailedMessage) {
+      setError((current) => current || runFailedMessage);
+    } else if (!succeeded && completedReceipt.failedTool) {
+      setError((current) => current || userFacingRunFailure("run_failed"));
+    }
+    if (succeeded) {
+      runOutcome = "succeeded";
+      await loadCaseSnapshot((turns) => {
+        if (turns.length) {
+          // D4 (BUG-1046): a turn the server wrote alongside this one (the
+          // one carrying the next question) joins the transcript too.
+          setMessages((current) => applySnapshotTurnsToMessages(
+            current,
+            turns,
+            (incoming) => messagesFromTurns(incoming as readonly PersistedTurn[]),
+          ));
+        }
+      });
+      onMessagesChange?.([
+        ...(action === "message" ? [{ role: "user" as const, text: trimmed }] : []),
+        { role: "assistant", text: parsed.text },
+      ]);
+      onCompleted?.();
+    } else {
+      await loadCaseSnapshot((turns) => {
+        if (turns.length) {
+          setMessages((current) => mergeTurnQuestions(current, turns));
+        }
+      });
+    }
+  } catch (caught) {
+    frames.settle();
+    const aborted = isAbortError(caught);
+    if (aborted) {
+      runOutcome = "stopped";
+      setMessages((current) => current.map((message) => {
+        if (message.renderKey !== assistantRenderKey) return message;
+        return {
+          ...message,
+          text: raw,
+          activityTrace: completeActivityTrace(activityTrace),
+          state: "settled" as const,
+          completedReceipt,
+          failed: false,
+          stopped: true,
+          turnId: completedTurnId,
+          activity: undefined,
+        };
+      }));
+      return;
+    }
+    setError("生时校正暂时不可用，请稍后再试。");
+    setMessages((current) => withdrawTypedMark(current).flatMap((message): RenderMessage[] => {
+      if (message.renderKey !== assistantRenderKey) return [message];
+      return hasActivityReceipt(completedReceipt)
+        ? [{
+          ...message,
+          text: "",
+          state: "settled",
+          completedReceipt,
+          failed: true,
+        }]
+        : [];
+    }));
+  } finally {
+    frames.dispose();
+    if (runAbort.current === abortController) runAbort.current = null;
+    lastRunOutcome.current = readonly ? "readonly" : runOutcome;
+    setPending(false);
+  }
+}
diff --git a/frontend/src/lib/rectification-chat-view.ts b/frontend/src/lib/rectification-chat-view.ts
new file mode 100644
index 00000000..f73da32c
--- /dev/null
+++ b/frontend/src/lib/rectification-chat-view.ts
@@ -0,0 +1,291 @@
+/**
+ * What the rectification chat surface shows this render, derived from its
+ * state: which message carries the regenerate button, the live choice card,
+ * the range delivery card, the read-only range, the question gap
+ * (preparing / unavailable / persisted question / collect-waiting /
+ * delivered / verified idle), where the persisted question hangs, and the
+ * timeline bar. Moved out of RectificationAgenticChat unchanged
+ * (TASK-rectification-code-split-20260926). Pure: the component applies the
+ * returned `nextOfferLock` itself; no React hooks here.
+ */
+import {
+  canShowRectificationReadonlyRange,
+  canShowRectificationSelectionCards,
+} from "@/lib/rectification-candidate-result";
+import { workingRectificationTime } from "@/lib/rectification-board-model";
+import {
+  RECTIFICATION_QUESTION_RETRY_LIMIT,
+  rectificationConversationState,
+  rectificationQuestionGapState,
+  interviewCollectWaiting,
+  interviewChoiceCardUnavailable,
+} from "@/lib/rectification-surface-state";
+import {
+  buildRectificationTimeline,
+  type RectificationTimelineStage,
+} from "@/lib/rectification-timeline-scale";
+import { postAdoptVerifyDoneCopy } from "@/lib/rectification-agentic/user-copy";
+import { isResumableStatus, type RectificationCaseStatus } from "@/lib/rectification-agentic/v9/case-status";
+import type { RectificationChoiceCard as ChoiceCardModel } from "@/lib/rectification-agentic/v9/choice-card";
+import {
+  interviewQuestionBlocksAdoptOffer,
+  nextSelectionCardLock,
+  questionIsAnswered,
+  resolveSelectionCardMessageKey,
+  turnQuestionFromCurrent,
+  type SelectionCardLock,
+} from "@/lib/rectification-agentic/v9/turn-question";
+import { placePersistedQuestion } from "@/lib/rectification-snapshot-messages";
+import { isSettledAssistantMessage } from "@/lib/rectification-chat-messages";
+import type { CandidateResult, CurrentQuestionModel } from "@/lib/rectification-chat-snapshot";
+import type { RenderMessage } from "@/components/rectification-message-entry";
+
+export type RectificationChatViewInput = Readonly<{
+  messages: RenderMessage[];
+  busy: boolean;
+  readonly: boolean;
+  regeneratingMessageKey: string | null;
+  shouldStartOpening: boolean;
+  openingRequested: boolean;
+  acceptingCandidateId: string | null;
+  selectionOfferLock: SelectionCardLock | null;
+  candidateResult: CandidateResult;
+  currentQuestion: CurrentQuestionModel | null;
+  questionSource: "focus" | "unavailable" | null;
+  choiceCard: ChoiceCardModel | null;
+  caseStatus: RectificationCaseStatus | null;
+  caseSnapshotLoaded: boolean;
+  searchWindow: readonly [string, string] | null;
+  caseStage: RectificationTimelineStage | null;
+  nextUserActionId: string | null;
+  interviewStopReason: string | null;
+  interviewSessionOutcome: string | null;
+  questionRetryAttempts: number;
+  savedTime: string | null;
+}>;
+
+export function deriveRectificationChatView(input: RectificationChatViewInput) {
+  const {
+    messages,
+    busy,
+    readonly,
+    regeneratingMessageKey,
+    shouldStartOpening,
+    openingRequested,
+    acceptingCandidateId,
+    selectionOfferLock,
+    candidateResult,
+    currentQuestion,
+    questionSource,
+    choiceCard,
+    caseStatus,
+    caseSnapshotLoaded,
+    searchWindow,
+    caseStage,
+    nextUserActionId,
+    interviewStopReason,
+    interviewSessionOutcome,
+    questionRetryAttempts,
+    savedTime,
+  } = input;
+  const latestRegeneratableKey = [...messages]
+    .reverse()
+    .find((message) => (
+      message.role === "assistant"
+      && message.state === "settled"
+      && !message.failed
+      && Boolean(message.turnId)
+      && Boolean(message.text)
+    ))?.renderKey;
+  const latestSettledAssistant = [...messages]
+    .reverse()
+    .find((message) => (
+      message.role === "assistant"
+      && message.state === "settled"
+      && !message.failed
+      && Boolean(message.text)
+    ));
+  const latestLiveQuestion = [...messages].reverse().find((message) => (
+    message.role === "assistant"
+    && message.question
+    && !questionIsAnswered(message.question)
+  ))?.question ?? null;
+  const showLiveChoiceCard = Boolean(
+    latestLiveQuestion
+    && latestLiveQuestion.options?.length === 4
+    && currentQuestion?.focus_id === latestLiveQuestion.focus_id
+    && choiceCard
+    && choiceCard.focus_id === latestLiveQuestion.focus_id
+    && (latestLiveQuestion.kind === "choice" || latestLiveQuestion.kind === "reverse_verify")
+    && !busy
+    && !readonly
+    && regeneratingMessageKey === null,
+  );
+  const canOfferCards = canShowRectificationSelectionCards(candidateResult);
+  // Cheap arithmetic over at most a dozen candidate minutes; recomputed with
+  // the render rather than memoised, matching the rest of this component.
+  const timelineView = buildRectificationTimeline({
+    searchWindow,
+    credibleRange: candidateResult?.credibleRange ?? null,
+    candidateTimes: candidateResult?.candidates.map((candidate) => candidate.time) ?? [],
+    inferenceMarks: candidateResult?.inferenceMarks ?? [],
+    stage: caseStage,
+    // The same call the board's title-row clock makes, on the same result, so
+    // the bar and `.rectification-board__clock` are one number by construction
+    // rather than by two code paths that happen to agree today.
+    workingTime: workingRectificationTime(candidateResult),
+    workingAdopted: Boolean(candidateResult?.selectedTime),
+    answeredProbeCount: candidateResult?.answeredProbeCount ?? null,
+    datedEventCount: candidateResult?.rangeDelivery?.event_count ?? null,
+  });
+  const persistedOfferKey = [...messages].reverse().find((message) => message.candidateOffer)?.renderKey;
+  const liveSelectionCardKey = persistedOfferKey
+    ?? (canOfferCards && !candidateResult?.selectedTime ? latestSettledAssistant?.renderKey : undefined);
+  // RectificationAgenticChat stores this lock during render (BUG-620); the
+  // comment on why sits next to that setSelectionOfferLock call.
+  const nextOfferLock = nextSelectionCardLock(selectionOfferLock, {
+    resultId: candidateResult?.resultId,
+    key: liveSelectionCardKey,
+  });
+  const selectionCardMessageKey = resolveSelectionCardMessageKey({
+    persistedOfferKey,
+    fallbackKey: latestSettledAssistant?.renderKey,
+    locked: nextOfferLock,
+    resultId: candidateResult?.resultId,
+    selectedTime: candidateResult?.selectedTime,
+    canOffer: canOfferCards,
+  });
+  // Adopt already has in-card “正在采用…” / “已采用”; hiding the whole card
+  // for `busy` is what made the three columns vanish on 「更像这个」.
+  const keepSelectionCardsWhileBusy = Boolean(
+    acceptingCandidateId || candidateResult?.selectedTime,
+  );
+  const liveInterviewBlockingAdopt = Boolean(
+    candidateResult
+    && !candidateResult.selectedTime
+    && messages.some((message) => (
+      interviewQuestionBlocksAdoptOffer(message.question, false)
+    )),
+  );
+  const showSelectionCards = Boolean(
+    candidateResult
+    && caseSnapshotLoaded
+    && (!busy || keepSelectionCardsWhileBusy)
+    && selectionCardMessageKey
+    && (canOfferCards || Boolean(candidateResult.selectedTime))
+  );
+  const showReadonlyRange = Boolean(
+    canShowRectificationReadonlyRange(candidateResult)
+    && latestSettledAssistant
+    && !showSelectionCards,
+  );
+  const collectSpokenPrompt = currentQuestion?.kind === "collect_spoken"
+    ? currentQuestion.prompt
+    : null;
+  const resumableCase = caseStatus !== null && isResumableStatus(caseStatus);
+  const deadChoice = interviewChoiceCardUnavailable({
+    questionKind: currentQuestion?.kind,
+    hasChoiceCard: Boolean(choiceCard),
+    questionId: currentQuestion?.question_id,
+  });
+  const liveQuestionOnMessages = Boolean(
+    latestSettledAssistant
+    && latestSettledAssistant.question
+    && currentQuestion
+    && latestSettledAssistant.question.focus_id === currentQuestion.focus_id
+    && !questionIsAnswered(latestSettledAssistant.question)
+    && !deadChoice,
+  );
+  // The gap between a settled turn and its next question has two visible
+  // states: `preparing` (one live timeline row, timed refetches) and
+  // `unavailable` (copy and a repair button) — never bare copy telling the
+  // reader to wait for the server. Collect-waiting is the training-gate gap:
+  // no next card, keep the case open, do not show 「没有拿到下一个问题」.
+  const collectWaiting = interviewCollectWaiting({
+    stopReason: interviewStopReason,
+    sessionOutcome: interviewSessionOutcome ?? candidateResult?.sessionOutcome ?? null,
+    questionMissing: currentQuestion === null,
+    offeringCards: showSelectionCards,
+  });
+  // BUG-917: the same judgement the message entry makes, read off the latest
+  // settled assistant message: a tap question nobody can answer any more.
+  const unansweredDeadChoiceOnMessages = Boolean(
+    latestSettledAssistant?.question
+    && (latestSettledAssistant.question.kind === "choice"
+      || latestSettledAssistant.question.kind === "reverse_verify")
+    && !latestSettledAssistant.question.answer_option
+    && (latestSettledAssistant.question.status === "active"
+      || latestSettledAssistant.question.status === "superseded")
+    && !liveQuestionOnMessages,
+  );
+  const questionGap = rectificationQuestionGapState({
+    liveQuestionVisible: liveQuestionOnMessages,
+    unansweredDeadChoice: unansweredDeadChoiceOnMessages,
+    questionMissing: currentQuestion === null,
+    questionLoadFailed: questionSource === "unavailable" || deadChoice,
+    questionPersisted: Boolean(currentQuestion?.prompt && questionSource === "focus") && !deadChoice,
+    offerAwaitingReader: showSelectionCards && !candidateResult?.selectedTime && currentQuestion === null,
+    nextUserActionId,
+    collectWaiting: collectWaiting && !deadChoice,
+    sessionOutcome: interviewSessionOutcome ?? candidateResult?.sessionOutcome ?? null,
+    stopReason: interviewStopReason,
+    deadChoice,
+    questionId: currentQuestion?.question_id ?? null,
+    hasChoiceCard: Boolean(choiceCard),
+    busy,
+    readonly,
+    regenerating: regeneratingMessageKey !== null,
+    snapshotLoaded: caseSnapshotLoaded,
+    resumableCase,
+    retryAttempts: questionRetryAttempts,
+    retryLimit: RECTIFICATION_QUESTION_RETRY_LIMIT,
+  });
+  // BUG-1046 (D3): the persisted question is drawn once. With an assistant
+  // message to carry it, it hangs there (BUG-678's intent) and other copies of
+  // the same focus come off; the standalone block is only the fallback when
+  // nothing can carry it. The gap state itself is unchanged.
+  const persistedTurnQuestion = questionGap === "persisted_question"
+    ? turnQuestionFromCurrent(currentQuestion, choiceCard)
+    : null;
+  const placedQuestion = persistedTurnQuestion
+    ? placePersistedQuestion(messages, persistedTurnQuestion, isSettledAssistantMessage)
+    : null;
+  const placedByKey = placedQuestion && placedQuestion.messages !== messages
+    ? new Map(placedQuestion.messages.map((message) => [message.renderKey, message]))
+    : null;
+  const showStandaloneQuestion = questionGap === "persisted_question"
+    && (placedQuestion ? placedQuestion.standalone : true);
+  const verifiedIdleCopy = questionGap === "verified_idle"
+    ? postAdoptVerifyDoneCopy(
+      savedTime,
+      messages.some((message) => message.question?.kind === "reverse_verify"),
+    )
+    : null;
+  const conversationState = rectificationConversationState({
+    messageCount: messages.length,
+    busy,
+    readonly,
+    shouldStartOpening,
+    openingStarted: openingRequested,
+  });
+  return {
+    latestRegeneratableKey,
+    latestSettledAssistant,
+    showLiveChoiceCard,
+    timelineView,
+    nextOfferLock,
+    selectionCardMessageKey,
+    liveInterviewBlockingAdopt,
+    showSelectionCards,
+    showReadonlyRange,
+    collectSpokenPrompt,
+    liveQuestionOnMessages,
+    questionGap,
+    placedByKey,
+    showStandaloneQuestion,
+    verifiedIdleCopy,
+    conversationState,
+  };
+}
+
+export type RectificationChatView = ReturnType<typeof deriveRectificationChatView>;
diff --git a/frontend/tests/account-dialog-inert-20260918.test.ts b/frontend/tests/account-dialog-inert-20260918.test.ts
index 320fb73d..6548a38e 100644
--- a/frontend/tests/account-dialog-inert-20260918.test.ts
+++ b/frontend/tests/account-dialog-inert-20260918.test.ts
@@ -28,6 +28,7 @@ import {
   USER_ID,
   fakeAccounting,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const read = (relativePath: string) => readFileSync(new URL(relativePath, import.meta.url), "utf8");
 
@@ -131,7 +132,8 @@ test("GET /api/rectification/cases/[caseId] warns JSON on every non-200 branch (
 });
 
 test("a 503 snapshot miss shows status copy and 重新读取, not collect-waiting (BUG-969)", () => {
-  const chat = read("../src/components/rectification-agentic-chat.tsx");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.equal(RECTIFICATION_SNAPSHOT_UNAVAILABLE_COPY, "这一问还没读到。");
   assert.equal(RECTIFICATION_SNAPSHOT_RETRY_LABEL, "重新读取");
   assert.match(chat, /RECTIFICATION_SNAPSHOT_UNAVAILABLE_COPY/);
diff --git a/frontend/tests/agent-voice-copy-contract.test.ts b/frontend/tests/agent-voice-copy-contract.test.ts
index 0778ceaf..76812437 100644
--- a/frontend/tests/agent-voice-copy-contract.test.ts
+++ b/frontend/tests/agent-voice-copy-contract.test.ts
@@ -28,6 +28,7 @@ import { MACHINE_VOICE_LEXICON } from "../src/lib/rectification-agentic/v9/agent
 import { FORBIDDEN_RECORD_VERDICT_PHRASE } from "../src/lib/rectification-agentic/birth-time-provenance.ts";
 import { attachQuestionsToTurns } from "../src/lib/rectification-agentic/v9/turn-question.ts";
 import { CASE_ID, FOCUS_ID, TURN_ID } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 /** Task 0 frozen “before” snapshot: accident case f83d9b42, origin/staging @ 8617eb56. */
 export const ACCIDENT_CASE_BEFORE_COPY = {
@@ -156,7 +157,8 @@ test("question stem ownership stays on set-focus spokenPrompt, not a slot or a s
   const agent = readFileSync(new URL("../src/mastra/agentic-rectification.ts", import.meta.url), "utf8");
   const route = readFileSync(new URL("../src/app/api/rectification/agent/route.ts", import.meta.url), "utf8");
   const exit = readFileSync(new URL("../src/lib/rectification-agentic/v9/turn-exit.ts", import.meta.url), "utf8");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(agent, /用 rectification-set-focus 的 spokenPrompt 写出服务端给你的下一问/);
   assert.match(agent, /题干会作为同一条消息的下一段自动出现/);
   assert.match(agent, /开场轮：先 set-focus 写采集题的 spokenPrompt/);
@@ -258,7 +260,8 @@ test("settled assistant body with a focus has no question-mark sentences", () =>
 
 test("delivery narration is three sentences and the range card replaces minute cards", () => {
   const choice = readFileSync(new URL("../src/lib/rectification-agentic/v9/answer-choice.ts", import.meta.url), "utf8");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const card = readFileSync(new URL("../src/components/rectification-range-delivery.tsx", import.meta.url), "utf8");
   const accept = readFileSync(new URL("../src/app/api/rectification/cases/[caseId]/candidates/accept/route.ts", import.meta.url), "utf8");
   assert.doesNotMatch(choice, /withProspectiveWindows/);
@@ -350,7 +353,8 @@ test("opening body lists domains without years and the stem no longer lists year
   assert.ok(MACHINE_VOICE_LEXICON.includes("有关联"));
   assert.ok(MACHINE_VOICE_LEXICON.includes("弱关联"));
   assert.ok(MACHINE_VOICE_LEXICON.includes("还在收窄"));
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.doesNotMatch(chat, /还在收窄/);
 });
 
diff --git a/frontend/tests/chat-composer-queue.test.ts b/frontend/tests/chat-composer-queue.test.ts
index da69c507..4a258f7c 100644
--- a/frontend/tests/chat-composer-queue.test.ts
+++ b/frontend/tests/chat-composer-queue.test.ts
@@ -14,13 +14,13 @@ import {
 } from "../src/lib/queued-draft.ts";
 import { chatReplyAnnouncer } from "../src/lib/chat-reply-announcement.ts";
 import { RECTIFICATION_STOPPED_NOTICE } from "../src/lib/rectification-surface-state.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
+import { abortWiringOf } from "./rectification-chat-run-fixtures.ts";
 
 const page = readFileSync(new URL("../src/app/(app)/page.tsx", import.meta.url), "utf8");
 const composer = readFileSync(new URL("../src/components/chat-composer.tsx", import.meta.url), "utf8");
-const rectification = readFileSync(
-  new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-  "utf8",
-);
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const rectification = rectificationChatSurface;
 const consultationRun = readFileSync(
   new URL("../src/hooks/use-consultation-run.ts", import.meta.url),
   "utf8",
@@ -136,7 +136,7 @@ test("a queued card renders above the live textarea", () => {
   assert.match(html, /还想再问一句/);
 });
 
-test("rectification abort settles as stopped, not a failed alert", () => {
+test("rectification abort settles as stopped, not a failed alert", async () => {
   assert.match(rectification, /stopped: true/);
   assert.match(rectification, /failed: false,\s*stopped: true/);
   assert.doesNotMatch(rectification, /if \(raw\.trim\(\)\) setError\(RECTIFICATION_STOPPED_NOTICE\)/);
@@ -149,18 +149,18 @@ test("rectification abort settles as stopped, not a failed alert", () => {
   assert.match(messageRow, /className="message-stopped-notice"/);
   assert.equal(RECTIFICATION_STOPPED_NOTICE, "已停止，已生成的内容保留；本次不会扣点。");
   assert.match(rectification, /signal: abortController\.signal/);
-  const choiceFetch = rectification.slice(
-    rectification.indexOf("const submitStructuredChoice"),
-    rectification.indexOf("const acceptCandidate"),
-  );
-  assert.match(choiceFetch, /runAbort\.current = abortController/);
-  assert.match(choiceFetch, /signal: abortController\.signal/);
-  const adoptFetch = rectification.slice(
-    rectification.indexOf("const acceptCandidate"),
-    rectification.indexOf("async function copyMessage"),
-  );
-  assert.match(adoptFetch, /runAbort\.current = abortController/);
-  assert.match(adoptFetch, /signal: abortController\.signal/);
+  // 原值: 从 chat 源码切 submitStructuredChoice / acceptCandidate 两段，各匹配 `runAbort.current = abortController` 与 `signal: abortController.signal`。
+  // 新值: 调用 runRectificationStructuredChoice / runRectificationCandidateAccept（假 fetch）：请求带的 signal
+  //       就是 runAbort 里那个控制器的（停止按钮能掐断它），结束后 runAbort 清空。
+  // 原因: TASK-rectification-code-split-20260926 两段函数体原样搬进参数函数；行为断言覆盖接线本身。
+  const choiceWiring = await abortWiringOf("choice");
+  assert.equal(choiceWiring.url, "/api/rectification/agent");
+  assert.equal(choiceWiring.signalMatchesRunAbort, true);
+  assert.equal(choiceWiring.runAbortCleared, true);
+  const adoptWiring = await abortWiringOf("accept");
+  assert.match(adoptWiring.url, /\/api\/rectification\/cases\/[^/]+\/candidates\/accept$/);
+  assert.equal(adoptWiring.signalMatchesRunAbort, true);
+  assert.equal(adoptWiring.runAbortCleared, true);
   assert.equal(chatReplyAnnouncer("stopped"), "chat_notice_toast");
   assert.doesNotMatch(
     rectification.slice(rectification.indexOf("{error &&"), rectification.indexOf("{readonly &&")),
diff --git a/frontend/tests/chat-notice-and-scroll-contract.test.ts b/frontend/tests/chat-notice-and-scroll-contract.test.ts
index 74b48d3b..f241c65e 100644
--- a/frontend/tests/chat-notice-and-scroll-contract.test.ts
+++ b/frontend/tests/chat-notice-and-scroll-contract.test.ts
@@ -15,6 +15,7 @@ import {
   turnTailOverflow,
 } from "../src/hooks/use-conversation-scroll-anchor.ts";
 import { homeSurface } from "./home-surface.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const pageSource = readFileSync(new URL("../src/app/(app)/page.tsx", import.meta.url), "utf8");
 const noticeSource = readFileSync(new URL("../src/lib/chat-notice.ts", import.meta.url), "utf8");
@@ -255,7 +256,8 @@ test("the turn spacer trails the actions row instead of sitting between text and
   assert.ok(entry.indexOf("<ChatMessageActions") < entry.indexOf("<ConversationFollowUps"));
   const rectEntry = readFileSync(new URL("../src/components/rectification-message-entry.tsx", import.meta.url), "utf8");
   assert.ok(rectEntry.indexOf("<ChatMessageRow") < rectEntry.indexOf("<ChatMessageActions"));
-  const rectChat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const rectChat = rectificationChatSurface;
   assert.match(rectChat, /className="rectification-message-wrap rectification-message-entry"\s*>\s*<RectificationMessageEntry/);
 });
 
@@ -303,7 +305,8 @@ test("idle history does not write a spacer when the reader has only scrolled up"
 });
 
 test("consultation send and rectification new turns call pinLatestTurn", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const pins = chat.match(/conversationAnchor\.pinLatestTurn\(\)/g) ?? [];
   assert.ok(pins.length >= 3, `expected three pinLatestTurn calls, got ${pins.length}`);
   assert.doesNotMatch(chat, /conversation\.current\?\.scrollTo|element\.scrollTo/);
diff --git a/frontend/tests/chat-stream-layout.test.ts b/frontend/tests/chat-stream-layout.test.ts
index 312be9a4..b5eaebf5 100644
--- a/frontend/tests/chat-stream-layout.test.ts
+++ b/frontend/tests/chat-stream-layout.test.ts
@@ -4,6 +4,7 @@ import test from "node:test";
 
 import { chatMessageViews } from "../src/lib/chat-message-view.ts";
 import { homeSurface as pageSource } from "./home-surface.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 const transcriptSource = readFileSync(new URL("../src/components/chat-transcript.tsx", import.meta.url), "utf8");
 const globalStyles = readFileSync(new URL("../src/app/globals.css", import.meta.url), "utf8");
 const messageRowSource = readFileSync(new URL("../src/components/chat-message-row.tsx", import.meta.url), "utf8");
@@ -190,10 +191,8 @@ test("docks the composer inside the chat panel instead of floating over content"
 
 test("ordinary consultation replies reuse the shared Agent action bar", () => {
   const actionsSource = readFileSync(new URL("../src/components/chat-message-actions.tsx", import.meta.url), "utf8");
-  const rectificationChat = readFileSync(
-    new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-    "utf8",
-  );
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const rectificationChat = rectificationChatSurface;
   for (const label of ["赞", "踩", "复制回答", "重新生成回答"]) {
     assert.match(actionsSource, new RegExp(`aria-label="${label}"`));
   }
diff --git a/frontend/tests/composer-ime-contract.test.ts b/frontend/tests/composer-ime-contract.test.ts
index e47da1e9..7b8d40ef 100644
--- a/frontend/tests/composer-ime-contract.test.ts
+++ b/frontend/tests/composer-ime-contract.test.ts
@@ -1,12 +1,11 @@
 import assert from "node:assert/strict";
 import { readFileSync } from "node:fs";
 import test from "node:test";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const page = readFileSync(new URL("../src/app/(app)/page.tsx", import.meta.url), "utf8");
-const rectification = readFileSync(
-  new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-  "utf8",
-);
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const rectification = rectificationChatSurface;
 const guide = readFileSync(new URL("../src/components/birth-time-guide-turn.tsx", import.meta.url), "utf8");
 
 function onKeyDownBlock(source: string, marker: string) {
diff --git a/frontend/tests/composer-isolation-contract.test.ts b/frontend/tests/composer-isolation-contract.test.ts
index c6d663bc..0ae71e58 100644
--- a/frontend/tests/composer-isolation-contract.test.ts
+++ b/frontend/tests/composer-isolation-contract.test.ts
@@ -3,6 +3,7 @@ import { readFileSync } from "node:fs";
 import test from "node:test";
 
 import { homeSurface as pageSource } from "./home-surface.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 const composerSource = readFileSync(new URL("../src/components/chat-composer.tsx", import.meta.url), "utf8");
 const draftStoreSource = readFileSync(new URL("../src/lib/composer-draft.ts", import.meta.url), "utf8");
 // 原值：homeSurface 连同独立 /people 表单一起检查聊天根草稿。
@@ -57,10 +58,8 @@ test("the textarea lives in an isolated composer that owns the draft subscriptio
   // subscription; a surface with its own draft (rectification) may pass `value` instead, and
   // must never write the main chat's store (BUG-477).
   assert.match(composerSource, /const storeDraft = useComposerDraft\(\);\n\s*const draft = value \?\? storeDraft;/);
-  const rectificationSource = readFileSync(
-    new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-    "utf8",
-  );
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const rectificationSource = rectificationChatSurface;
   assert.match(rectificationSource, /<ChatComposer[\s\S]*?value=\{draft\}/);
   assert.doesNotMatch(rectificationSource, /composer-draft|setComposerDraft|useComposerDraft/);
 
diff --git a/frontend/tests/consultation-entrypoint.test.ts b/frontend/tests/consultation-entrypoint.test.ts
index 06daac3f..0a03636d 100644
--- a/frontend/tests/consultation-entrypoint.test.ts
+++ b/frontend/tests/consultation-entrypoint.test.ts
@@ -11,6 +11,7 @@ import {
   shouldLoadGeneralDailyPanchanga,
 } from "../src/lib/consultation-entrypoint.ts";
 import { homeSurface } from "./home-surface.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 test("plain consultation questions remain user-authored", () => {
   // Given: an ordinary question without a product entrypoint.
@@ -184,7 +185,8 @@ test("homepage birth-time card opens the V9 Agentic surface via the server case
 test("homepage mounts the Agentic surface without invoking retired rectification starters", () => {
   const page = homeSurface;
   const component = readFileSync(new URL("../src/components/conversational-birth-time-rectification.tsx", import.meta.url), "utf8");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
 
   assert.match(page, /<ConversationalBirthTimeRectification/);
   assert.match(component, /<RectificationAgenticChat/);
@@ -290,7 +292,8 @@ test("an answered conversation offers no suggested follow-up questions", () => {
 
 test("rectify-first handoffs stay as Agent context", () => {
   const source = homeSurface;
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
 
   // 原值：pendingConsultationQuestion={rectificationPendingQuestion} 写在 page.tsx JSX
   // 新值：pendingConsultationQuestion: rectificationPendingQuestion 写在 hook 的 panel
@@ -467,7 +470,8 @@ test("the starter home hides technical chart parameters", () => {
 
 test("rectification 402 navigates to the membership page with the rectification source", () => {
   // Given: the Agentic rectification chat owns the /api/rectification/agent call.
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const membershipLib = readFileSync(new URL("../src/lib/membership.ts", import.meta.url), "utf8");
 
   // 原值: 402 后 window.location.assign(membershipHref("rectification"))
diff --git a/frontend/tests/rectification-activity-receipt.test.ts b/frontend/tests/rectification-activity-receipt.test.ts
index c186ce24..83b31867 100644
--- a/frontend/tests/rectification-activity-receipt.test.ts
+++ b/frontend/tests/rectification-activity-receipt.test.ts
@@ -6,6 +6,14 @@ import {
   reduceRectificationActivityReceipt,
   receiptFromRectificationActivityState,
 } from "../src/lib/rectification-activity-receipt";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
+import type { RenderMessage } from "../src/components/rectification-message-entry.tsx";
+import {
+  chatRunRecorder,
+  ndjsonResponse,
+  runRectificationChatTurn,
+  withFakeFetch,
+} from "./rectification-chat-run-fixtures.ts";
 
 test("a successful retry clears the same tool's earlier failure", () => {
   let state = createRectificationActivityReceiptState();
@@ -89,30 +97,47 @@ test("a later failure removes methods contributed by the failed tool", () => {
   });
 });
 
-const chatSource = readFileSync(
-  new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-  "utf8",
-);
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chatSource = rectificationChatSurface;
 
-test("answer deltas preserve a still-running server activity", () => {
-  const deltaBranch = chatSource.slice(
-    chatSource.indexOf('event.type === "answer.delta"'),
-    chatSource.indexOf('event.type === "run.failed"'),
-  );
+test("answer deltas preserve a still-running server activity", async () => {
   // Former locks: `state: raw.trim() ? "streaming" : "thinking"` and `text: raw,` inside the
   // delta branch. Those pinned one setMessages per network chunk (BUG-473); the same state
   // derivation now lives in the frame buffer's flush, which the delta branch feeds.
-  const frameFlush = chatSource.slice(
-    chatSource.indexOf("const frames = createStreamFrameBuffer"),
-    chatSource.indexOf("const abortController = new AbortController()"),
-  );
-  assert.match(frameFlush, /state: text\.trim\(\) \? "streaming" : "thinking"/);
-  assert.match(frameFlush, /^\s*text,$/m);
-  assert.match(deltaBranch, /frames\.setAnswer\(raw\)/);
-  assert.match(deltaBranch, /event\.replace === true \? event\.text : raw \+ event\.text/);
-  assert.doesNotMatch(deltaBranch, /settled\.spoken/);
-  assert.match(deltaBranch, /正在组织回答/);
-  assert.doesNotMatch(deltaBranch, /activeActivity:\s*undefined/);
+  // 原值: 从 chat 源码切 answer.delta 分支（到 run.failed）与 frames 定义（到 new AbortController），匹配
+  //       flush 里 `state: text.trim() ? "streaming" : "thinking"`、`text,`，delta 分支里 `frames.setAnswer(raw)`、
+  //       `event.replace === true ? event.text : raw + event.text`、「正在组织回答」，且不含 settled.spoken /
+  //       `activeActivity: undefined`。
+  // 新值: 调用 runRectificationChatTurn（假 NDJSON 流）：
+  //       1) 只有工具开始、没有正文时，flush 出的活行是 thinking、正文为空；
+  //       2) 两段 answer.delta（第二段 replace）后，flush 出的活行是 streaming、正文等于 replace 后的全文、
+  //          活动标签是「正在组织回答…」且活动没被清掉；每段 delta 不各自 setMessages（一次提交）。
+  // 原因: TASK-rectification-code-split-20260926 `send` 函数体原样搬进 rectification-chat-turn-run.ts；
+  //       对流读取结果断言比源码 token 更强。
+  const liveRows = (history: RenderMessage[][]) => history
+    .map((messages) => messages.find((message) => message.renderKey === "v9-assistant-1"))
+    .filter((row): row is RenderMessage => Boolean(row));
+
+  const toolOnly = chatRunRecorder();
+  await withFakeFetch(() => ndjsonResponse([
+    { type: "tool.activity", tool: "rectification-read-case", status: "started" },
+  ]), () => runRectificationChatTurn(toolOnly.turnDeps(), "message", "我 2019 年换了工作"));
+  const thinkingRow = liveRows(toolOnly.messageHistory).find((row) => row.state === "thinking" && row.activityTrace?.length);
+  assert.ok(thinkingRow, "the flush of a tool-only stream keeps a thinking row");
+  assert.equal(thinkingRow.text, "");
+
+  const streamed = chatRunRecorder();
+  await withFakeFetch(() => ndjsonResponse([
+    { type: "tool.activity", tool: "rectification-read-case", status: "started" },
+    { type: "answer.delta", text: "第一段" },
+    { type: "answer.delta", text: "改写后的全文", replace: true },
+  ]), () => runRectificationChatTurn(streamed.turnDeps(), "message", "我 2019 年换了工作"));
+  const streamingRows = liveRows(streamed.messageHistory).filter((row) => row.state === "streaming");
+  assert.equal(streamingRows.length, 1, "deltas commit through the frame buffer, not one setMessages each");
+  assert.equal(streamingRows[0].text, "改写后的全文");
+  assert.match(streamingRows[0].activity?.label ?? "", /正在组织回答/);
+  assert.equal(streamingRows[0].activity?.phase, "answer-composition");
+  assert.ok(streamed.liveLabels.includes("正在组织回答…"));
 });
 
 test("failed server turns retain their receipt state without parsing activity from answer text", () => {
diff --git a/frontend/tests/rectification-adopt-cards-stay-20260909.test.ts b/frontend/tests/rectification-adopt-cards-stay-20260909.test.ts
index 8f174d37..2f18403f 100644
--- a/frontend/tests/rectification-adopt-cards-stay-20260909.test.ts
+++ b/frontend/tests/rectification-adopt-cards-stay-20260909.test.ts
@@ -1,28 +1,51 @@
 import assert from "node:assert/strict";
 import { readFileSync } from "node:fs";
 import test from "node:test";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
+import { deriveRectificationChatView } from "../src/lib/rectification-chat-view.ts";
+import { chatViewInput, offerableCandidateResult, settledAssistant } from "./rectification-chat-run-fixtures.ts";
 
 const read = (relativePath: string) => readFileSync(new URL(relativePath, import.meta.url), "utf8");
 
-const chat = read("../src/components/rectification-agentic-chat.tsx");
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chat = rectificationChatSurface;
 const delivery = read("../src/components/rectification-range-delivery.tsx");
 const styles = read("../src/app/globals.css");
-const showBlock = chat.slice(
-  chat.indexOf("const keepSelectionCardsWhileBusy"),
-  chat.indexOf("const showReadonlyRange"),
-);
 const messageLoop = chat.slice(
   chat.indexOf("{messages.map((message) => {"),
   chat.indexOf("{savedTime &&"),
 );
 
 test("clicking 更像这个 does not unmount the range card for busy", () => {
-  assert.match(showBlock, /acceptingCandidateId \|\| candidateResult\?\.selectedTime/);
-  assert.match(showBlock, /!busy \|\| keepSelectionCardsWhileBusy/);
-  assert.doesNotMatch(
-    showBlock,
-    /&& !busy\s*&& selectionCardMessageKey/,
-  );
+  // 原值: 从 chat 源码切 `const keepSelectionCardsWhileBusy` 到 `const showReadonlyRange`，匹配
+  //       `acceptingCandidateId || candidateResult?.selectedTime`、`!busy || keepSelectionCardsWhileBusy`，
+  //       且不含 `&& !busy && selectionCardMessageKey`。
+  // 新值: 调用 deriveRectificationChatView：可交付结果挂在最新已结算回复上——空闲出卡；busy 且没在采用、
+  //       没采用则收卡；busy 但正在采用（acceptingCandidateId）或已采用（带持久 offer）时卡仍在。
+  // 原因: TASK-rectification-code-split-20260926 派生逻辑原样搬到 rectification-chat-view.ts（纯函数）；
+  //       行为断言覆盖原三条 token 的意图，且更强。
+  const result = offerableCandidateResult();
+  const messages = [settledAssistant("offer-1")];
+  const idle = deriveRectificationChatView(chatViewInput({ messages, candidateResult: result }));
+  assert.equal(idle.showSelectionCards, true);
+  assert.equal(idle.selectionCardMessageKey, "offer-1");
+  const busyTurn = deriveRectificationChatView(chatViewInput({ messages, candidateResult: result, busy: true }));
+  assert.equal(busyTurn.showSelectionCards, false);
+  const adopting = deriveRectificationChatView(chatViewInput({
+    messages,
+    candidateResult: result,
+    busy: true,
+    acceptingCandidateId: result.candidates[0].candidateId,
+  }));
+  assert.equal(adopting.showSelectionCards, true);
+  assert.equal(adopting.selectionCardMessageKey, "offer-1");
+  const adopted = deriveRectificationChatView(chatViewInput({
+    messages: [settledAssistant("offer-1", { candidateOffer: { resultId: result.resultId } })],
+    candidateResult: { ...result, selectedTime: "04:53" },
+    busy: true,
+  }));
+  assert.equal(adopted.showSelectionCards, true);
+  assert.equal(adopted.selectionCardMessageKey, "offer-1");
 });
 
 test("after adopt the card stays on the locked offering message", () => {
diff --git a/frontend/tests/rectification-adopt-flow-20260902.test.ts b/frontend/tests/rectification-adopt-flow-20260902.test.ts
index 36a4cd35..0eaa5305 100644
--- a/frontend/tests/rectification-adopt-flow-20260902.test.ts
+++ b/frontend/tests/rectification-adopt-flow-20260902.test.ts
@@ -44,6 +44,7 @@ import {
   rectificationLiveProgressLabel,
 } from "../src/lib/rectification-activity-labels.ts";
 import { OPEN_ENGINE_CAPABILITY_CEILING, CASE_ID, FOCUS_ID, TURN_ID, USER_ID, fakeAccounting } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const preAdopt = JSON.parse(readFileSync(
   new URL("./fixtures/rectification-case-bf7a8de6-pre-adopt.json", import.meta.url),
@@ -397,10 +398,8 @@ test("skipped collect questions stay attached to their asked turn", () => {
 });
 
 test("chat owns adopt cards on the offering message and drops the list-end handoff", () => {
-  const chat = readFileSync(
-    new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-    "utf8",
-  );
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(chat, /canShowRectificationSelectionCards/);
   assert.match(chat, /canShowRectificationReadonlyRange/);
   assert.match(chat, /candidateOffer/);
diff --git a/frontend/tests/rectification-adopt-flow-fix-20260903.test.ts b/frontend/tests/rectification-adopt-flow-fix-20260903.test.ts
index 64c0728f..a0d7bb23 100644
--- a/frontend/tests/rectification-adopt-flow-fix-20260903.test.ts
+++ b/frontend/tests/rectification-adopt-flow-fix-20260903.test.ts
@@ -25,6 +25,7 @@ import {
   fakeAccounting,
   receiptHandlers,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const STYLE_OPTIONS = [
   { label: "明确发生且时间吻合", answer_class: "yes" as const },
@@ -280,10 +281,8 @@ test("adopt_representative nonterminal exit stays satisfied without a new questi
 });
 
 test("adopted time is shown on the card row, not a composer status bar", () => {
-  const chat = readFileSync(
-    new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-    "utf8",
-  );
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const styles = readFileSync(new URL("../src/app/globals.css", import.meta.url), "utf8");
   // 原值: 「改选」是状态条按钮，滚动到出卡消息
   // 新值: 点其他候选行即改选；无 rectification-adopt-status
@@ -364,10 +363,8 @@ test("consult handoff button and startConsultationAfterRectification are gone",
       assert.equal(source.includes(token), false, `${file} still contains ${token}`);
     }
   }
-  const chat = readFileSync(
-    new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-    "utf8",
-  );
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   // 原值: 状态条「之后新建对话即按此时间排盘」
   // 新值: 无状态条；采用后旁白走 postAdoptVerifyDoneCopy；开场仍可预告结束后新建对话
   // 原因: BUG-595 决策 3
diff --git a/frontend/tests/rectification-agentic-entry.test.ts b/frontend/tests/rectification-agentic-entry.test.ts
index d2823ecd..9d788ded 100644
--- a/frontend/tests/rectification-agentic-entry.test.ts
+++ b/frontend/tests/rectification-agentic-entry.test.ts
@@ -2,16 +2,28 @@ import assert from "node:assert/strict";
 import { readFileSync } from "node:fs";
 import test from "node:test";
 import { homeSurface as page } from "./home-surface.ts";
+import { createElement } from "react";
+import { renderToStaticMarkup } from "react-dom/server";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
+import {
+  abortWiringOf,
+  chatViewInput,
+  fixtureChoiceCard,
+  offerableCandidateResult,
+  RUN_FOCUS_ID,
+  settledAssistant,
+} from "./rectification-chat-run-fixtures.ts";
+import { deriveRectificationChatView } from "../src/lib/rectification-chat-view.ts";
+import { completedReceiptFromPersisted } from "../src/lib/rectification-chat-messages.ts";
+import { RectificationQuestionGapNotices } from "../src/components/rectification-question-gap-notices.tsx";
 
 const component = readFileSync(
   new URL("../src/components/conversational-birth-time-rectification.tsx", import.meta.url),
   "utf8",
 );
 const surfaceState = readFileSync(new URL("../src/lib/rectification-surface-state.ts", import.meta.url), "utf8");
-const chat = readFileSync(
-  new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-  "utf8",
-);
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chat = rectificationChatSurface;
 const messageEntry = readFileSync(
   new URL("../src/components/rectification-message-entry.tsx", import.meta.url),
   "utf8",
@@ -362,15 +374,29 @@ test("Agentic rectification follows the conversation tail only while the reader
 });
 
 test("rectification keeps receipts for the varga sentence and shows live tool progress", () => {
-  const activityHelper = chat.slice(
-    chat.indexOf("function completedReceiptFromPersisted"),
-    chat.indexOf("export function RectificationAgenticChat"),
-  );
-  assert.match(activityHelper, /receipt\.tools/);
-  assert.doesNotMatch(activityHelper, /receipt\.phases/);
-  assert.match(activityHelper, /filter\(isPublicRectificationTool\)/);
-  assert.match(activityHelper, /receipt\.methods/);
-  assert.match(activityHelper, /filter\(isPublicRectificationMethod\)/);
+  // 原值: 从 chat 源码切 `function completedReceiptFromPersisted` 到 `export function RectificationAgenticChat`，
+  //       匹配 receipt.tools / receipt.methods / filter(isPublicRectificationTool) / filter(isPublicRectificationMethod)，且不含 receipt.phases。
+  // 新值: 直接调用 completedReceiptFromPersisted：旧形状回执只留公开工具（去重）与公开方法，phases 不进步骤；
+  //       tool_activities 形状只收 completed / failed 的公开工具与公开方法。
+  // 原因: TASK-rectification-code-split-20260926 把该函数原样搬到 rectification-chat-messages.ts；对返回值断言强于源码 token。
+  const legacyReceipt = completedReceiptFromPersisted({
+    status: "completed",
+    phases: ["case.loaded", "run.completed"],
+    tools: ["rectification-read-case", "internal-debug-tool", "rectification-read-case"],
+    methods: ["d1-rashi", "not-a-public-method"],
+  });
+  assert.deepEqual(legacyReceipt, { steps: ["rectification-read-case"], methods: ["d1-rashi"] });
+  const activityReceipt = completedReceiptFromPersisted({
+    status: "completed",
+    phases: ["case.loaded"],
+    tools: ["rectification-set-focus"],
+    tool_activities: [
+      { tool: "rectification-read-case", status: "completed", methods: ["d1-rashi", "not-a-public-method"] },
+      { tool: "internal-debug-tool", status: "completed" },
+      { tool: "rectification-set-focus", status: "started" },
+    ],
+  });
+  assert.deepEqual(activityReceipt, { steps: ["rectification-read-case"], methods: ["d1-rashi"] });
   // 原值: 上述 token 都在 rectification-agentic-chat.tsx 的 messages.map 内。
   // 新值: RenderMessage / 时间轴 / varga 句随行组件抽出。
   // 原因: BUG-725 已结算行记忆化，派生不得留在容器每帧计算。
@@ -643,19 +669,25 @@ test("rectification composer can stop a live agent run", () => {
   assert.match(messageEntry, /showActivity=\{displayedMessage\.state !== "settled"\}/);
 });
 
-test("aborting a live run marks the bubble stopped without an alert", () => {
+test("aborting a live run marks the bubble stopped without an alert", async () => {
   assert.match(chat, /failed: false,\s*stopped: true/);
   // 原值: 停止提示 prop 写在容器 map 的 ChatMessageRow 上。
   // 新值: 同一表达式在行组件内。
   // 原因: BUG-725。
   assert.match(messageEntry, /stoppedNotice=\{message\.stopped \? RECTIFICATION_STOPPED_NOTICE : undefined\}/);
   assert.doesNotMatch(chat, /role="alert"[\s\S]{0,80}RECTIFICATION_STOPPED_NOTICE/);
-  const choiceFetch = chat.slice(chat.indexOf("const submitStructuredChoice"), chat.indexOf("const acceptCandidate"));
-  assert.match(choiceFetch, /runAbort\.current = abortController/);
-  assert.match(choiceFetch, /signal: abortController\.signal/);
-  const adoptFetch = chat.slice(chat.indexOf("const acceptCandidate"), chat.indexOf("async function copyMessage"));
-  assert.match(adoptFetch, /runAbort\.current = abortController/);
-  assert.match(adoptFetch, /signal: abortController\.signal/);
+  // 原值: 从 chat 源码切 submitStructuredChoice / acceptCandidate 两段，各匹配 `runAbort.current = abortController` 与 `signal: abortController.signal`。
+  // 新值: 调用 runRectificationStructuredChoice / runRectificationCandidateAccept（假 fetch）：请求带的 signal
+  //       就是 runAbort 里那个控制器的（停止按钮能掐断它），结束后 runAbort 清空。
+  // 原因: TASK-rectification-code-split-20260926 两段函数体原样搬进参数函数；行为断言覆盖接线本身。
+  const choiceWiring = await abortWiringOf("choice");
+  assert.equal(choiceWiring.url, "/api/rectification/agent");
+  assert.equal(choiceWiring.signalMatchesRunAbort, true);
+  assert.equal(choiceWiring.runAbortCleared, true);
+  const adoptWiring = await abortWiringOf("accept");
+  assert.match(adoptWiring.url, /\/api\/rectification\/cases\/[^/]+\/candidates\/accept$/);
+  assert.equal(adoptWiring.signalMatchesRunAbort, true);
+  assert.equal(adoptWiring.runAbortCleared, true);
 });
 
 test("conversation and house board reuse the quiet overlay scrollbar", () => {
@@ -696,14 +728,22 @@ test("time-selection cards use server adoption state and stay mutually exclusive
   assert.match(chat, /keepSelectionCardsWhileBusy/);
   assert.match(chat, /\.reverse\(\)\.find\(\(message\) => message\.candidateOffer\)/);
   assert.match(chat, /showLiveChoiceCard = Boolean\([\s\S]*latestLiveQuestion[\s\S]*options\?\.length === 4[\s\S]*!busy/);
-  assert.match(
-    chat.slice(chat.indexOf("const showSelectionCards"), chat.indexOf("const collectSpokenPrompt")),
-    /!busy \|\| keepSelectionCardsWhileBusy/,
-  );
-  assert.doesNotMatch(
-    chat.slice(chat.indexOf("const showSelectionCards"), chat.indexOf("const collectSpokenPrompt")),
-    /offeredSelectionOnce/,
+  // 原值: 从 chat 源码切 `const showSelectionCards` 到 `const collectSpokenPrompt`：含
+  //       `!busy || keepSelectionCardsWhileBusy`，不含 `offeredSelectionOnce`。
+  // 新值: 调用 deriveRectificationChatView：busy 收卡、busy 但正在采用留卡；同一输入先后派生两次结果相同，
+  //       出过一次卡不会留下隐藏记忆。
+  // 原因: TASK-rectification-code-split-20260926 派生逻辑原样搬进纯函数 rectification-chat-view.ts。
+  const offerable = offerableCandidateResult();
+  const offerMessages = [settledAssistant("offer-1")];
+  const offerIdle = chatViewInput({ messages: offerMessages, candidateResult: offerable });
+  assert.equal(deriveRectificationChatView(offerIdle).showSelectionCards, true);
+  assert.equal(deriveRectificationChatView({ ...offerIdle, busy: true }).showSelectionCards, false);
+  assert.equal(
+    deriveRectificationChatView({ ...offerIdle, busy: true, acceptingCandidateId: offerable.candidates[0].candidateId }).showSelectionCards,
+    true,
   );
+  // 出过卡、采用中之后再来一轮 busy：仍收卡，没有 offeredSelectionOnce 式的记忆。
+  assert.equal(deriveRectificationChatView({ ...offerIdle, busy: true }).showSelectionCards, false);
   assert.match(chat, /!candidateResult\?\.selectedTime \? latestSettledAssistant\?\.renderKey/);
   // 原值: showSelectionCards && message.renderKey === selectionCardMessageKey
   // 新值: 还要有 candidateResult 才渲染行选卡
@@ -716,10 +756,32 @@ test("time-selection cards use server adoption state and stay mutually exclusive
   assert.match(messageEntry, /variant="embedded"/);
   assert.match(messageEntry, /choiceNonce/);
   assert.match(messageEntry, /question\.answer_option/);
-  assert.match(messageLoop, /<RectificationChoiceCard/);
-  assert.match(messageLoop, /variant="embedded"/);
-  assert.match(messageLoop, /choiceNonce/);
+  // 原值: messageLoop（容器 map 到 savedTime 之间）含 persisted 题卡 <RectificationChoiceCard / variant="embedded" / choiceNonce。
+  // 新值: messageLoop 挂 <RectificationQuestionGapNotices 并传 choiceNonce；真渲染该块：persisted 选择题出嵌入卡（is-embedded、四个选项）。
+  // 原因: TASK-rectification-code-split-20260926 缺题块（含 persisted 题卡）抽成组件，位置不变。
+  assert.match(messageLoop, /<RectificationQuestionGapNotices/);
+  assert.match(messageLoop, /choiceNonce=\{choiceNonce\}/);
+  const persistedCard = fixtureChoiceCard();
+  const persistedHtml = renderToStaticMarkup(createElement(RectificationQuestionGapNotices, {
+    view: { showStandaloneQuestion: true, questionGap: "persisted_question", showSelectionCards: false, verifiedIdleCopy: null },
+    currentQuestion: { kind: "choice", prompt: persistedCard.prompt, focus_id: RUN_FOCUS_ID, question_id: persistedCard.question_id },
+    choiceCard: persistedCard,
+    choiceNonce: 0,
+    busy: false,
+    readonly: false,
+    snapshotFailure: null,
+    questionRepairAttempts: 0,
+    questionRepairing: false,
+    submitChoice() {},
+    submitStop() {},
+    async refetchQuestion() {},
+    async repairQuestion() {},
+  }));
+  assert.match(persistedHtml, /data-testid="persisted-question"/);
+  assert.match(persistedHtml, /class="rectification-choice-card is-embedded"/);
+  assert.equal(persistedHtml.match(/class="birth-time-choice-option is-primary"/g)?.length, 4);
   assert.doesNotMatch(messageLoop, /rectification-question-slot/);
+  assert.doesNotMatch(persistedHtml, /rectification-question-slot/);
   assert.doesNotMatch(messageEntry, /rectification-question-slot/);
   assert.doesNotMatch(choiceCardComponent, /setSelectedKey\(""\)/);
   assert.match(choiceCardComponent, /selectedKey/);
diff --git a/frontend/tests/rectification-answer-choice.test.ts b/frontend/tests/rectification-answer-choice.test.ts
index 78222885..cce6b708 100644
--- a/frontend/tests/rectification-answer-choice.test.ts
+++ b/frontend/tests/rectification-answer-choice.test.ts
@@ -53,6 +53,7 @@ import {
   fakeAccounting,
   receiptHandlers,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const ACTION_ID = "aaaaaaaa-aaaa-4aaa-8aaa-aaaaaaaaaaaa";
 const QUESTION_ID = "question-1";
@@ -1477,7 +1478,8 @@ test("the public agent route treats structured choice as a non-model command", (
   assert.match(route, /SKIP_PROBE_ACTION/);
   assert.doesNotMatch(route, /action === "skip_probe"[\s\S]{0,80}paused/);
   assert.match(route, /export const maxDuration = 240/);
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(chat, /isPersistedFocusId\(focusId\)/);
   assert.match(chat, /focusId,/);
   assert.match(chat, /shouldContinueAfterStructuredChoice\(payload\?\.nextAction, payload\)/);
diff --git a/frontend/tests/rectification-chat-run-fixtures.ts b/frontend/tests/rectification-chat-run-fixtures.ts
new file mode 100644
index 00000000..d5118ead
--- /dev/null
+++ b/frontend/tests/rectification-chat-run-fixtures.ts
@@ -0,0 +1,361 @@
+/**
+ * Fake dependencies for the rectification chat's parameter functions
+ * (TASK-rectification-code-split-20260926). The split moved `send`,
+ * `submitStructuredChoice` and `acceptCandidate` out of the component into
+ * `runRectificationChatTurn`, `runRectificationStructuredChoice` and
+ * `runRectificationCandidateAccept`; tests that used to slice those bodies out
+ * of the component source now call the functions with these fakes and assert
+ * on what they do (requests, abort wiring, transcript, error line).
+ */
+import type { SetStateAction } from "react";
+
+import type { RenderMessage } from "../src/components/rectification-message-entry.tsx";
+import {
+  runRectificationChatTurn,
+  type RectificationChatTurnDeps,
+  type RectificationRunOutcome,
+  type RectificationTurnAction,
+  type RectificationTurnContinuation,
+} from "../src/lib/rectification-chat-turn-run.ts";
+import {
+  runRectificationStructuredChoice,
+  type RectificationStructuredChoiceDeps,
+} from "../src/lib/rectification-chat-choice-run.ts";
+import {
+  runRectificationCandidateAccept,
+  type RectificationCandidateAcceptDeps,
+} from "../src/lib/rectification-chat-accept-run.ts";
+import type { CandidateResult, CurrentQuestionModel } from "../src/lib/rectification-chat-snapshot.ts";
+import { parseRectificationCandidateResult } from "../src/lib/rectification-candidate-result.ts";
+import type { RectificationChatViewInput } from "../src/lib/rectification-chat-view.ts";
+import type { RectificationChoiceCard } from "../src/lib/rectification-agentic/v9/choice-card.ts";
+
+export const RUN_CASE_ID = "44444444-4444-4444-8444-444444444444";
+export const RUN_SESSION_ID = "33333333-3333-4333-8333-333333333333";
+export const RUN_FOCUS_ID = "aaaaaaaa-aaaa-4aaa-8aaa-aaaaaaaaaaa1";
+
+export type RecordedState<T> = Readonly<{
+  get: () => T;
+  set: (next: SetStateAction<T>) => void;
+}>;
+
+export function recordedState<T>(initial: T): RecordedState<T> {
+  let value = initial;
+  return {
+    get: () => value,
+    set: (next) => {
+      value = typeof next === "function" ? (next as (current: T) => T)(value) : next;
+    },
+  };
+}
+
+export type FetchCall = Readonly<{ url: string; init: RequestInit | undefined; body: Record<string, unknown> | null }>;
+
+/**
+ * Swap `fetch` (and the `window` frame scheduler the stream buffer needs) for
+ * the duration of `run`. `respond` sees each call in order.
+ */
+export async function withFakeFetch<T>(
+  respond: (call: FetchCall, index: number) => Response | Promise<Response>,
+  run: (calls: FetchCall[]) => Promise<T>,
+): Promise<T> {
+  const calls: FetchCall[] = [];
+  const originalFetch = globalThis.fetch;
+  const globals = globalThis as { window?: unknown };
+  const originalWindow = globals.window;
+  globalThis.fetch = (async (input: RequestInfo | URL, init?: RequestInit) => {
+    const body = typeof init?.body === "string" ? JSON.parse(init.body) as Record<string, unknown> : null;
+    const call = { url: String(input), init, body };
+    calls.push(call);
+    return respond(call, calls.length - 1);
+  }) as typeof fetch;
+  globals.window = {
+    requestAnimationFrame: (callback: () => void) => setTimeout(callback, 0),
+    cancelAnimationFrame: (handle: ReturnType<typeof setTimeout>) => clearTimeout(handle),
+    setTimeout,
+    clearTimeout,
+  };
+  try {
+    return await run(calls);
+  } finally {
+    globalThis.fetch = originalFetch;
+    globals.window = originalWindow;
+  }
+}
+
+export function ndjsonResponse(events: readonly Record<string, unknown>[], init: ResponseInit = {}): Response {
+  return new Response(`${events.map((event) => JSON.stringify(event)).join("\n")}\n`, {
+    status: 200,
+    headers: { "content-type": "application/x-ndjson; charset=utf-8" },
+    ...init,
+  });
+}
+
+export function jsonResponse(payload: unknown, status = 200): Response {
+  return new Response(JSON.stringify(payload), {
+    status,
+    headers: { "content-type": "application/json" },
+  });
+}
+
+/** Everything the three run functions write, recorded for assertions. */
+export function chatRunRecorder(initialMessages: RenderMessage[] = []) {
+  const transcript = recordedState<RenderMessage[]>(initialMessages);
+  /** Every transcript the run committed, in order (each setMessages call). */
+  const messageHistory: RenderMessage[][] = [];
+  const messages: RecordedState<RenderMessage[]> = {
+    get: transcript.get,
+    set: (next) => {
+      transcript.set(next);
+      messageHistory.push(transcript.get());
+    },
+  };
+  const error = recordedState("");
+  const choiceNonce = recordedState(0);
+  const nextUserActionId = recordedState<string | null>(null);
+  const acceptingCandidateId = recordedState<string | null>(null);
+  const candidateResult = recordedState<CandidateResult>(null);
+  const savedTime = recordedState<string | null>(null);
+  const savedStatus = recordedState<"accepted" | "confirmed" | null>(null);
+  const pending: boolean[] = [];
+  const liveLabels: string[] = [];
+  const snapshotLoads: Array<((turns: readonly unknown[]) => void) | undefined> = [];
+  const pins: number[] = [];
+  const sends: Array<Readonly<{ action: RectificationTurnAction; messageText: string; continuation?: RectificationTurnContinuation }>> = [];
+  const completed: number[] = [];
+  const profileIncomplete: number[] = [];
+  const billing: Array<{ source?: string } | undefined> = [];
+  const messageChanges: unknown[] = [];
+  const saved: Array<[string, string]> = [];
+  const refs = {
+    keyCounter: { current: 0 },
+    currentQuestionRef: { current: null as CurrentQuestionModel | null },
+    runAbort: { current: null as AbortController | null },
+    lastRunOutcome: { current: null as RectificationRunOutcome },
+  };
+  const shared = {
+    caseId: RUN_CASE_ID,
+    sessionId: RUN_SESSION_ID,
+    busy: false,
+    readonly: false,
+    ...refs,
+    conversationAnchor: { pinLatestTurn: () => { pins.push(Date.now()); } },
+    setError: error.set,
+    setMessages: messages.set,
+    setPending: (value: boolean) => { pending.push(value); },
+    beginLiveRun: (label: string) => { liveLabels.push(label); },
+    loadCaseSnapshot: async (merge?: (turns: readonly unknown[]) => void) => {
+      snapshotLoads.push(merge);
+      merge?.([]);
+      return undefined;
+    },
+    send: async (action: RectificationTurnAction, messageText: string, continuation?: RectificationTurnContinuation) => {
+      sends.push({ action, messageText, continuation });
+    },
+    onCompleted: () => { completed.push(1); },
+    onProfileIncomplete: () => { profileIncomplete.push(1); },
+    onMessagesChange: (next: unknown) => { messageChanges.push(next); },
+  };
+
+  function turnDeps(overrides: Partial<RectificationChatTurnDeps> = {}): RectificationChatTurnDeps {
+    return {
+      ...shared,
+      selectedModelId: "model-a",
+      conversationReadonly: false,
+      rememberLiveActivity: (label: string) => { liveLabels.push(label); return label; },
+      onOpenBilling: (options?: { source?: string }) => { billing.push(options); },
+      ...overrides,
+    };
+  }
+
+  function choiceDeps(
+    choiceCard: RectificationChoiceCard | null,
+    overrides: Partial<RectificationStructuredChoiceDeps> = {},
+  ): RectificationStructuredChoiceDeps {
+    return {
+      ...shared,
+      choiceCard,
+      currentQuestion: null,
+      actionIdForChoice: () => globalThis.crypto.randomUUID(),
+      setChoiceNonce: choiceNonce.set,
+      setNextUserActionId: nextUserActionId.set,
+      ...overrides,
+    };
+  }
+
+  function acceptDeps(overrides: Partial<RectificationCandidateAcceptDeps> = {}): RectificationCandidateAcceptDeps {
+    return {
+      ...shared,
+      candidateResult: candidateResult.get(),
+      acceptingCandidateId: acceptingCandidateId.get(),
+      setAcceptingCandidateId: acceptingCandidateId.set,
+      setCandidateResult: candidateResult.set,
+      setSavedTime: savedTime.set,
+      setSavedStatus: savedStatus.set,
+      onSaved: (time: string, status: string) => { saved.push([time, status]); },
+      ...overrides,
+    };
+  }
+
+  return {
+    messages,
+    messageHistory,
+    error,
+    choiceNonce,
+    nextUserActionId,
+    acceptingCandidateId,
+    candidateResult,
+    savedTime,
+    savedStatus,
+    pending,
+    liveLabels,
+    snapshotLoads,
+    pins,
+    sends,
+    completed,
+    profileIncomplete,
+    billing,
+    messageChanges,
+    saved,
+    refs,
+    turnDeps,
+    choiceDeps,
+    acceptDeps,
+  };
+}
+
+export function fixtureChoiceCard(overrides: Partial<RectificationChoiceCard> = {}): RectificationChoiceCard {
+  return {
+    question_id: "distinguish:1",
+    method_id: "candidate_discriminator",
+    prompt: "2023 年前后，有没有换过工作或职责明显变化？",
+    why: "",
+    varga: null,
+    choice_mode: "A/B/C/D",
+    options: [
+      { key: "A", label: "明确发生且时间吻合" },
+      { key: "B", label: "发生过但程度较弱" },
+      { key: "C", label: "没有这回事" },
+      { key: "D", label: "这段记不清楚" },
+    ],
+    stop_label: "先这样，先看当前范围",
+    stop_message: "",
+    scoring: true,
+    probe_id: "probe:1",
+    case_revision: 3,
+    focus_id: RUN_FOCUS_ID,
+    ...overrides,
+  } as RectificationChoiceCard;
+}
+
+export function fixtureCandidateResult(): NonNullable<CandidateResult> {
+  return {
+    resultId: "result-1",
+    candidates: [
+      { candidateId: "cand-1", time: "05:07" },
+      { candidateId: "cand-2", time: "05:15" },
+    ],
+    selectedTime: null,
+  } as unknown as NonNullable<CandidateResult>;
+}
+
+/**
+ * Where the stop button's AbortController goes during a tapped choice or an
+ * adoption: is the controller in `runAbort` the one whose signal the request
+ * carries, and is it cleared once the run ends?
+ */
+export async function abortWiringOf(kind: "choice" | "accept") {
+  const recorder = chatRunRecorder();
+  let signalMatchesRunAbort = false;
+  let url = "";
+  await withFakeFetch((call) => {
+    url = call.url;
+    signalMatchesRunAbort = Boolean(
+      recorder.refs.runAbort.current
+      && call.init?.signal === recorder.refs.runAbort.current.signal,
+    );
+    return jsonResponse({ ok: false }, 500);
+  }, async () => {
+    if (kind === "choice") {
+      await runRectificationStructuredChoice(recorder.choiceDeps(fixtureChoiceCard()), "answer_choice", "A");
+    } else {
+      recorder.candidateResult.set(fixtureCandidateResult());
+      await runRectificationCandidateAccept(recorder.acceptDeps(), "cand-1");
+    }
+  });
+  return {
+    url,
+    signalMatchesRunAbort,
+    runAbortCleared: recorder.refs.runAbort.current === null,
+  };
+}
+
+/**
+ * A result the delivery card may offer: `completed_with_range` with selection
+ * allowed, parsed by the real parser (same snapshot shape as
+ * rectification-delivery-vs-collect-20260914.test.ts).
+ */
+export function offerableCandidateResult(overrides: Record<string, unknown> = {}): NonNullable<CandidateResult> {
+  const result = parseRectificationCandidateResult({
+    resultId: "11111111-1111-4111-8111-111111111111",
+    candidates: [
+      { candidateId: "88888888-8888-4888-8888-888888888881", rank: 1, time: "04:53", relativeSupport: 16, tiedMinuteCount: 2 },
+      { candidateId: "88888888-8888-4888-8888-888888888882", rank: 2, time: "05:00", relativeSupport: 16, tiedMinuteCount: 2 },
+    ],
+    overallConfidence: "medium",
+    selectionAllowed: true,
+    canAdopt: false,
+    confirmationAllowed: false,
+    representativeTime: "04:53",
+    selectedTime: null,
+    selectionKind: null,
+    credibleRange: ["04:48", "05:07"],
+    session_outcome: "completed_with_range",
+    decisionReceipt: {
+      display_allowed: true,
+      selection_allowed: true,
+      acceptance_allowed: true,
+      propose_allowed: true,
+      confirmation_allowed: false,
+      accept_allowed: true,
+      confirm_allowed: false,
+    },
+    ...overrides,
+  });
+  if (!result) throw new Error("offerableCandidateResult: parser rejected the fixture");
+  return result;
+}
+
+export function settledAssistant(renderKey: string, extra: Partial<RenderMessage> = {}): RenderMessage {
+  return { role: "assistant", text: `回复 ${renderKey}`, renderKey, state: "settled", ...extra };
+}
+
+/** Input for deriveRectificationChatView with a quiet, loaded, idle surface. */
+export function chatViewInput(overrides: Partial<RectificationChatViewInput> = {}): RectificationChatViewInput {
+  return {
+    messages: [],
+    busy: false,
+    readonly: false,
+    regeneratingMessageKey: null,
+    shouldStartOpening: false,
+    openingRequested: false,
+    acceptingCandidateId: null,
+    selectionOfferLock: null,
+    candidateResult: null,
+    currentQuestion: null,
+    questionSource: null,
+    choiceCard: null,
+    caseStatus: null,
+    caseSnapshotLoaded: true,
+    searchWindow: null,
+    caseStage: null,
+    nextUserActionId: null,
+    interviewStopReason: null,
+    interviewSessionOutcome: null,
+    questionRetryAttempts: 0,
+    savedTime: null,
+    ...overrides,
+  };
+}
+
+export { runRectificationChatTurn, runRectificationStructuredChoice, runRectificationCandidateAccept };
diff --git a/frontend/tests/rectification-chat-surface.ts b/frontend/tests/rectification-chat-surface.ts
new file mode 100644
index 00000000..40c10bf1
--- /dev/null
+++ b/frontend/tests/rectification-chat-surface.ts
@@ -0,0 +1,34 @@
+import { readFileSync } from "node:fs";
+
+/**
+ * The rectification chat surface as source text: the container component and
+ * the hooks, parameter functions and blocks it was split into
+ * (TASK-rectification-code-split-20260926). Same idea as `home-surface.ts`:
+ * a whole-source contract that held on `rectification-agentic-chat.tsx`
+ * before the split holds on this concatenation after it, because the code is
+ * the same code in more files. Slices between two anchors do not survive the
+ * split; those tests call the extracted functions instead.
+ */
+export const rectificationChatSurfaceFiles = [
+  "../src/components/rectification-agentic-chat.tsx",
+  "../src/components/rectification-question-gap-notices.tsx",
+  "../src/hooks/use-rectification-case-snapshot.ts",
+  "../src/hooks/use-rectification-board-layout.ts",
+  "../src/hooks/use-rectification-live-activity.ts",
+  "../src/lib/rectification-chat-messages.ts",
+  "../src/lib/rectification-chat-snapshot.ts",
+  "../src/lib/rectification-chat-turn-run.ts",
+  "../src/lib/rectification-chat-choice-run.ts",
+  "../src/lib/rectification-chat-accept-run.ts",
+  "../src/lib/rectification-chat-message-actions.ts",
+  "../src/lib/rectification-chat-question-repair.ts",
+  "../src/lib/rectification-chat-view.ts",
+] as const;
+
+export function readRectificationChatFile(relativePath: (typeof rectificationChatSurfaceFiles)[number]): string {
+  return readFileSync(new URL(relativePath, import.meta.url), "utf8");
+}
+
+export const rectificationChatSurface = rectificationChatSurfaceFiles
+  .map((relativePath) => readRectificationChatFile(relativePath))
+  .join("\n");
diff --git a/frontend/tests/rectification-dead-d9-choice-20260916.test.ts b/frontend/tests/rectification-dead-d9-choice-20260916.test.ts
index 567122ab..a6c80c0c 100644
--- a/frontend/tests/rectification-dead-d9-choice-20260916.test.ts
+++ b/frontend/tests/rectification-dead-d9-choice-20260916.test.ts
@@ -30,6 +30,7 @@ import {
 } from "../src/lib/rectification-agentic/v9/varga-distinguish-probe.ts";
 import { rectificationQuestionGapState } from "../src/lib/rectification-surface-state.ts";
 import { FOCUS_ID } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const OWNED_KEY = "d9_relationship:relationship_style";
 const QUESTION_ID = "d9_relationship:relationship_style:score";
@@ -449,10 +450,8 @@ test("a dead tap card never shares the screen with the collect-wait placeholder
     rectificationQuestionGapState({ ...base, unansweredDeadChoice: true }),
     "unavailable",
   );
-  const chat = readFileSync(
-    new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-    "utf8",
-  );
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(chat, /unansweredDeadChoice: unansweredDeadChoiceOnMessages,/);
   assert.match(chat, /latestSettledAssistant\.question\.status === "superseded"/);
   const entry = readFileSync(
diff --git a/frontend/tests/rectification-delivery-ui-simplify-20260908.test.ts b/frontend/tests/rectification-delivery-ui-simplify-20260908.test.ts
index 2c4a915c..b4c94e6a 100644
--- a/frontend/tests/rectification-delivery-ui-simplify-20260908.test.ts
+++ b/frontend/tests/rectification-delivery-ui-simplify-20260908.test.ts
@@ -15,6 +15,7 @@ import {
   resetDeliveryTurnGuardForTests,
 } from "../src/lib/rectification-agentic/v9/delivery-turn-guard.ts";
 import { RectificationVerificationReport } from "../src/components/rectification-verification-report.tsx";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 test("delivery body is three sentences and omits the eight-method report", () => {
   const text = deliveryTurnNarration({
@@ -101,7 +102,8 @@ test("agent-run trims evidence after persistNextInterviewIfIdle so delivery can
 });
 
 test("composer wrap no longer hosts 先这样 or the adopt status bar", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const wrap = chat.slice(chat.indexOf("className=\"composer-wrap\""), chat.indexOf("className=\"composer-footer\""));
   assert.doesNotMatch(wrap, /CHOICE_STOP_LABEL/);
   assert.doesNotMatch(wrap, /rectification-collect-stop/);
diff --git a/frontend/tests/rectification-engine-version-cross-midnight.test.ts b/frontend/tests/rectification-engine-version-cross-midnight.test.ts
index 2d42627e..7b7805d0 100644
--- a/frontend/tests/rectification-engine-version-cross-midnight.test.ts
+++ b/frontend/tests/rectification-engine-version-cross-midnight.test.ts
@@ -22,6 +22,7 @@ import {
   CASE_ID, SESSION_ID, TURN_ID, USER_ID, FOCUS_ID,
   computeFixture, dossierFixture, fakeAccounting, receiptHandlers,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 // Real native-engine response, using explicitly fictional input, not a hand-built contract.
 const golden = JSON.parse(readFileSync(new URL(
@@ -234,7 +235,8 @@ test("stale history exposes explicit recompare and real tools replace old proven
   assert.equal(refreshed.case.result_identity.read_only, false);
   assert.equal(refreshed.case.result_identity.algorithm_version, CURRENT);
   assert.equal(refreshed.case.result_identity.policy_version, golden.versions.decision_policy_version);
-  const component = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const component = rectificationChatSurface;
   assert.match(component, /resultNotice && canRecompare && !historyReadonly/);
   assert.match(component, /recompareHistoricalResult\(\{ canRecompare, historyReadonly, busy, send \}\)/);
   assert.match(component, /if \(\(action === "message" && !trimmed\) \|\| conversationReadonly\) return/);
diff --git a/frontend/tests/rectification-exhaustion-exit-20260906.test.ts b/frontend/tests/rectification-exhaustion-exit-20260906.test.ts
index 40971ef9..d601d80b 100644
--- a/frontend/tests/rectification-exhaustion-exit-20260906.test.ts
+++ b/frontend/tests/rectification-exhaustion-exit-20260906.test.ts
@@ -36,6 +36,10 @@ import {
   fakeAccounting,
   receiptHandlers,
 } from "./rectification-v9-test-support.ts";
+import { createElement } from "react";
+import { renderToStaticMarkup } from "react-dom/server";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
+import { RectificationReadonlyRange } from "../src/components/rectification-question-gap-notices.tsx";
 
 const EXISTENCE_OPTIONS = [
   { label: "明确发生且时间吻合", answer_class: "yes" as const },
@@ -632,12 +636,20 @@ test("collect spoken stop stays on choice cards; range line is status only", ()
   // 原值: 口述停止按钮和范围小字共用 CHOICE_STOP_LABEL / onStop
   // 新值: CHOICE_STOP_LABEL 只在选择题卡；composer-wrap 不再挂先这样
   // 原因: BUG-595 决策 2
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const route = readFileSync(new URL("../src/app/api/rectification/agent/route.ts", import.meta.url), "utf8");
-  const rangeFn = chat.slice(
-    chat.indexOf("function RectificationReadonlyRange"),
-    chat.indexOf("type RectificationAgenticChatProps"),
-  );
+  // 原值: 从 chat 源码切 `function RectificationReadonlyRange` 到 `type RectificationAgenticChatProps`，
+  //       断言含 role="status"、不含 onStop / <button。
+  // 新值: 真渲染 RectificationReadonlyRange：输出是 role="status" 的一行，没有按钮、没有停止入口。
+  // 原因: TASK-rectification-code-split-20260926 该组件原样搬到 rectification-question-gap-notices.tsx；渲染断言强于源码切片。
+  const rangeFn = renderToStaticMarkup(createElement(RectificationReadonlyRange, {
+    range: ["05:00", "05:20"],
+    sessionOutcome: null,
+    discriminatingEventProbes: null,
+    contrastProbes: null,
+  }));
+  assert.match(rangeFn, /^<p class="rectification-readonly-range" role="status">[^<]*<\/p>$/);
   const wrap = chat.slice(chat.indexOf("className=\"composer-wrap\""), chat.indexOf("className=\"composer-footer\""));
   assert.doesNotMatch(wrap, /rectification-collect-stop/);
   // 原值: 容器源码含 CHOICE_STOP_LABEL。
@@ -649,7 +661,7 @@ test("collect spoken stop stays on choice cards; range line is status only", ()
   assert.match(chat, /function submitStop/);
   assert.match(chat, /RectificationReadonlyRange/);
   assert.match(rangeFn, /role="status"/);
-  assert.doesNotMatch(rangeFn, /onStop/);
+  assert.doesNotMatch(rangeFn, /onStop|先这样/);
   assert.doesNotMatch(rangeFn, /<button/);
   assert.match(route, /ask_about_result/);
   assert.match(route, /STOP_ACTION/);
diff --git a/frontend/tests/rectification-growth-contract.test.ts b/frontend/tests/rectification-growth-contract.test.ts
new file mode 100644
index 00000000..8ffbe2a9
--- /dev/null
+++ b/frontend/tests/rectification-growth-contract.test.ts
@@ -0,0 +1,88 @@
+import assert from "node:assert/strict";
+import { readFileSync } from "node:fs";
+import test from "node:test";
+
+/**
+ * Growth caps for the three rectification files split by
+ * TASK-rectification-code-split-20260926, same shape as
+ * home-shell-growth-contract.test.ts: a coarse line guardrail (measured
+ * baseline + 150) plus hook-count caps that stop state from drifting back
+ * into the container. Line counts are `\n` counts, same as `wc -l`.
+ * Hook counts use `\buseX[<(]` so `useState<Type>(` is not missed.
+ */
+
+const read = (relativePath: string) => readFileSync(new URL(relativePath, import.meta.url), "utf8");
+
+function lineCount(source: string): number {
+  return (source.match(/\n/g) ?? []).length;
+}
+
+function countMatches(source: string, pattern: RegExp): number {
+  return source.match(new RegExp(pattern.source, "g"))?.length ?? 0;
+}
+
+function sourceFrom(source: string, marker: string): string {
+  const start = source.indexOf(marker);
+  assert.notEqual(start, -1, `missing marker: ${marker}`);
+  return source.slice(start);
+}
+
+const REACT_HOOK_CALL = /\buse(?:State|Ref|Effect|LayoutEffect|InsertionEffect|Callback|Memo|Reducer|Context|Id|Transition|DeferredValue|SyncExternalStore|Optimistic|ActionState)\s*[<(]/;
+
+// ---------------------------------------------------------------------------
+// T1 · rectification-agentic-chat.tsx
+// Measured 2026-09-26 on codex/rectification-code-split-20260926 after the
+// component split. Before (origin/staging 12cbe6f8): file 2043 lines, component
+// body 1625 lines, useState 35, useRef 16, useEffect 7, useLayoutEffect 2,
+// useCallback 12. After: file 737, body 630, useState 12, useRef 9,
+// useEffect 5, useLayoutEffect 0, useCallback 6.
+const CHAT_PATH = "../src/components/rectification-agentic-chat.tsx";
+const CHAT_LINE_BASELINE = 737;
+const CHAT_LINE_CAP = CHAT_LINE_BASELINE + 150;
+/** D2 of the task: the component body stays at or under 900 lines. */
+const CHAT_BODY_LINE_CAP = 900;
+const CHAT_USE_STATE_CAP = 12;
+const CHAT_USE_REF_CAP = 9;
+const CHAT_EFFECT_CAP = 5;
+const CHAT_USE_CALLBACK_CAP = 6;
+const CHAT_COMPONENT_MARKER = "export function RectificationAgenticChat(";
+
+/** Parameter functions split out of the chat; they take state and setters, never call hooks. */
+const CHAT_PARAMETER_MODULES = [
+  "../src/lib/rectification-chat-messages.ts",
+  "../src/lib/rectification-chat-snapshot.ts",
+  "../src/lib/rectification-chat-turn-run.ts",
+  "../src/lib/rectification-chat-choice-run.ts",
+  "../src/lib/rectification-chat-accept-run.ts",
+  "../src/lib/rectification-chat-message-actions.ts",
+  "../src/lib/rectification-chat-question-repair.ts",
+  "../src/lib/rectification-chat-view.ts",
+] as const;
+
+test("rectification-agentic-chat.tsx line count stays within the coarse guardrail", () => {
+  const n = lineCount(read(CHAT_PATH));
+  assert.ok(n <= CHAT_LINE_CAP, `rectification-agentic-chat.tsx has ${n} lines; cap is ${CHAT_LINE_CAP} (${CHAT_LINE_BASELINE} baseline + 150).`);
+});
+
+test("RectificationAgenticChat body stays at or under 900 lines", () => {
+  const n = lineCount(sourceFrom(read(CHAT_PATH), CHAT_COMPONENT_MARKER));
+  assert.ok(n <= CHAT_BODY_LINE_CAP, `RectificationAgenticChat body has ${n} lines; cap is ${CHAT_BODY_LINE_CAP}.`);
+});
+
+test("RectificationAgenticChat hook counts must not grow", () => {
+  const body = sourceFrom(read(CHAT_PATH), CHAT_COMPONENT_MARKER);
+  const useState = countMatches(body, /\buseState[<(]/);
+  const useRef = countMatches(body, /\buseRef[<(]/);
+  const effects = countMatches(body, /\buse(?:Layout)?Effect[<(]/);
+  const useCallback = countMatches(body, /\buseCallback[<(]/);
+  assert.ok(useState <= CHAT_USE_STATE_CAP, `useState ${useState}; cap ${CHAT_USE_STATE_CAP}. New state belongs in a hook such as use-rectification-case-snapshot.ts.`);
+  assert.ok(useRef <= CHAT_USE_REF_CAP, `useRef ${useRef}; cap ${CHAT_USE_REF_CAP}. Do not rewrite state as refs to dodge the useState cap.`);
+  assert.ok(effects <= CHAT_EFFECT_CAP, `useEffect + useLayoutEffect ${effects}; cap ${CHAT_EFFECT_CAP}.`);
+  assert.ok(useCallback <= CHAT_USE_CALLBACK_CAP, `useCallback ${useCallback}; cap ${CHAT_USE_CALLBACK_CAP}. Turn bodies belong in lib/rectification-chat-*-run.ts.`);
+});
+
+test("rectification chat parameter functions call no React hooks", () => {
+  for (const path of CHAT_PARAMETER_MODULES) {
+    assert.doesNotMatch(read(path), REACT_HOOK_CALL, `${path} must stay a parameter function module (no React hooks).`);
+  }
+});
diff --git a/frontend/tests/rectification-occupation-coverage-exit.test.ts b/frontend/tests/rectification-occupation-coverage-exit.test.ts
index f5a1778d..345c7c10 100644
--- a/frontend/tests/rectification-occupation-coverage-exit.test.ts
+++ b/frontend/tests/rectification-occupation-coverage-exit.test.ts
@@ -32,6 +32,7 @@ import {
   fakeAccounting,
   receiptHandlers,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const STYLE_OPTIONS = [
   { label: "明确发生且时间吻合", answer_class: "yes" as const },
@@ -825,7 +826,8 @@ test("idle persist on the covered-domain accident delivers adopt and writes no f
 
 test("agent-run still writes the exhaustion gate when idle persist returns terminalNote", () => {
   const agent = readFileSync(new URL("../src/lib/rectification-agentic/v9/agent-run.ts", import.meta.url), "utf8");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(agent, /interviewIdle\.terminalNote && interviewIdle\.hostNarration/);
   assert.match(agent, /persistExhaustionGateTurn/);
   assert.match(chat, /canOfferCards = canShowRectificationSelectionCards/);
diff --git a/frontend/tests/rectification-other-collect-fallback-20260908.test.ts b/frontend/tests/rectification-other-collect-fallback-20260908.test.ts
index 61b89440..3d97ce33 100644
--- a/frontend/tests/rectification-other-collect-fallback-20260908.test.ts
+++ b/frontend/tests/rectification-other-collect-fallback-20260908.test.ts
@@ -30,6 +30,7 @@ import {
   fakeAccounting,
   receiptHandlers,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 type ExecutableTool<T = unknown> = {
   execute(input: unknown): Promise<T>;
@@ -325,7 +326,8 @@ test("orphan collect:other focus is skipped so idle persist can deliver", async
 
 test("agent-run writes the exhaustion gate when idle persist returns terminalNote", () => {
   const agent = readFileSync(new URL("../src/lib/rectification-agentic/v9/agent-run.ts", import.meta.url), "utf8");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(agent, /interviewIdle\.terminalNote && interviewIdle\.hostNarration/);
   assert.match(agent, /persistExhaustionGateTurn/);
   assert.match(chat, /canOfferCards = canShowRectificationSelectionCards/);
diff --git a/frontend/tests/rectification-post-adopt-verify-20260904.test.ts b/frontend/tests/rectification-post-adopt-verify-20260904.test.ts
index 14c53633..85a44556 100644
--- a/frontend/tests/rectification-post-adopt-verify-20260904.test.ts
+++ b/frontend/tests/rectification-post-adopt-verify-20260904.test.ts
@@ -1,5 +1,4 @@
 import assert from "node:assert/strict";
-import { readFileSync } from "node:fs";
 import test from "node:test";
 
 import {
@@ -17,6 +16,11 @@ import {
   rectificationQuestionRetryActive,
   type RectificationQuestionGapInput,
 } from "../src/lib/rectification-surface-state.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
+import { createElement } from "react";
+import { renderToStaticMarkup } from "react-dom/server";
+import { RectificationQuestionGapNotices } from "../src/components/rectification-question-gap-notices.tsx";
+import { RECTIFICATION_QUESTION_RELOAD_LABEL } from "../src/lib/rectification-surface-state.ts";
 
 const STYLE_OPTIONS = [
   { label: "明确发生且时间吻合", answer_class: "yes" as const },
@@ -159,18 +163,37 @@ test("question gap: start_consultation is verified_idle; missing next_user_actio
 });
 
 test("verified_idle UI is a closing line without reload, gap copy, or consult handoff", () => {
-  const chat = readFileSync(
-    new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-    "utf8",
-  );
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(chat, /questionGap === "verified_idle"/);
   assert.match(chat, /postAdoptVerifyDoneCopy/);
   assert.match(chat, /skip_this_probe/);
   assert.match(chat, /SKIP_PROBE_ACTION/);
   assert.doesNotMatch(chat, /rectification-consult-handoff/);
-  const idle = chat.slice(chat.indexOf('questionGap === "verified_idle"'));
-  assert.doesNotMatch(idle.slice(0, 400), /rectification-question-gap__copy/);
-  assert.doesNotMatch(idle.slice(0, 400), /RECTIFICATION_QUESTION_RELOAD_LABEL/);
+  // 原值: 从 chat 源码第一处 `questionGap === "verified_idle"` 起取 400 字，断言不含
+  //       rectification-question-gap__copy 与 RECTIFICATION_QUESTION_RELOAD_LABEL。
+  // 新值: 真渲染缺题块（verified_idle + 收尾句、无对照卡）：只有一行 role="status" 的收尾句，
+  //       没有缺题文案、没有「接着问」重载按钮。
+  // 原因: TASK-rectification-code-split-20260926 该 JSX 原样搬进 rectification-question-gap-notices.tsx；
+  //       渲染断言比按字数截源码更准。
+  const idleHtml = renderToStaticMarkup(createElement(RectificationQuestionGapNotices, {
+    view: { showStandaloneQuestion: false, questionGap: "verified_idle", showSelectionCards: false, verifiedIdleCopy: "已按 05:07 核对完毕。" },
+    currentQuestion: null,
+    choiceCard: null,
+    choiceNonce: 0,
+    busy: false,
+    readonly: false,
+    snapshotFailure: null,
+    questionRepairAttempts: 0,
+    questionRepairing: false,
+    submitChoice() {},
+    submitStop() {},
+    async refetchQuestion() {},
+    async repairQuestion() {},
+  }));
+  assert.equal(idleHtml, '<p class="rectification-pending-note" role="status">已按 05:07 核对完毕。</p>');
+  assert.doesNotMatch(idleHtml, /rectification-question-gap__copy/);
+  assert.ok(!idleHtml.includes(RECTIFICATION_QUESTION_RELOAD_LABEL));
   // 原值: 状态条「已采用 {savedTime}」+「之后新建对话即按此时间排盘」
   // 新值: verified_idle 走 postAdoptVerifyDoneCopy；无核对题用新句
   // 原因: BUG-595 决策 3
diff --git a/frontend/tests/rectification-probe-replay-loss-20260908.test.ts b/frontend/tests/rectification-probe-replay-loss-20260908.test.ts
index e45469c9..5c749a2a 100644
--- a/frontend/tests/rectification-probe-replay-loss-20260908.test.ts
+++ b/frontend/tests/rectification-probe-replay-loss-20260908.test.ts
@@ -20,6 +20,9 @@ import {
   rangeWidthMinutes,
   withRangeChangedAfterEvidence,
 } from "../src/lib/rectification-agentic/user-copy.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
+import { deriveRectificationChatView } from "../src/lib/rectification-chat-view.ts";
+import { chatViewInput, offerableCandidateResult, settledAssistant } from "./rectification-chat-run-fixtures.ts";
 
 const S1_TIMES = [
   "04:50", "04:51", "04:52", "04:53", "04:54", "04:55", "04:56", "04:57", "05:13",
@@ -301,16 +304,21 @@ test("BUG-588 evidence narration names a widened range after compare", () => {
 });
 
 test("P3 selection cards stay gated by a loaded snapshot; adopt busy does not unmount them", () => {
-  const chat = readFileSync(
-    new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-    "utf8",
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
+  // 原值: 从 chat 源码切 `const showSelectionCards` 到 `const showReadonlyRange`，匹配
+  //       `!busy || keepSelectionCardsWhileBusy` 与 `caseSnapshotLoaded`。
+  // 新值: 调用 deriveRectificationChatView：快照未载入不出卡；载入后出卡；busy 收卡，正在采用时留卡。
+  // 原因: TASK-rectification-code-split-20260926 派生逻辑原样搬进纯函数 rectification-chat-view.ts。
+  const result = offerableCandidateResult();
+  const loaded = chatViewInput({ messages: [settledAssistant("offer-1")], candidateResult: result });
+  assert.equal(deriveRectificationChatView({ ...loaded, caseSnapshotLoaded: false }).showSelectionCards, false);
+  assert.equal(deriveRectificationChatView(loaded).showSelectionCards, true);
+  assert.equal(deriveRectificationChatView({ ...loaded, busy: true }).showSelectionCards, false);
+  assert.equal(
+    deriveRectificationChatView({ ...loaded, busy: true, acceptingCandidateId: result.candidates[0].candidateId }).showSelectionCards,
+    true,
   );
-  const block = chat.slice(
-    chat.indexOf("const showSelectionCards"),
-    chat.indexOf("const showReadonlyRange"),
-  );
-  assert.match(block, /!busy \|\| keepSelectionCardsWhileBusy/);
-  assert.match(block, /caseSnapshotLoaded/);
   assert.match(chat, /startTransition\(/);
 });
 
diff --git a/frontend/tests/rectification-question-in-message.test.ts b/frontend/tests/rectification-question-in-message.test.ts
index 5fc56128..e9260e1e 100644
--- a/frontend/tests/rectification-question-in-message.test.ts
+++ b/frontend/tests/rectification-question-in-message.test.ts
@@ -25,6 +25,7 @@ import {
   dossierFixture,
   fakeAccounting,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const OTHER_TURN = "44444444-4444-4444-8444-444444444444";
 
@@ -50,7 +51,8 @@ function choiceSchema(prompt: string) {
   };
 }
 
-const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chat = rectificationChatSurface;
 const row = readFileSync(new URL("../src/components/chat-message-row.tsx", import.meta.url), "utf8");
 const casesRoute = readFileSync(new URL("../src/app/api/rectification/cases/[caseId]/route.ts", import.meta.url), "utf8");
 const caseDossierResponse = readFileSync(new URL("../src/lib/rectification-agentic/v9/case-dossier-response.ts", import.meta.url), "utf8");
diff --git a/frontend/tests/rectification-question-ownership.test.ts b/frontend/tests/rectification-question-ownership.test.ts
index 5e03d990..5b361fe8 100644
--- a/frontend/tests/rectification-question-ownership.test.ts
+++ b/frontend/tests/rectification-question-ownership.test.ts
@@ -46,6 +46,7 @@ import {
   fakeAccounting,
   receiptHandlers,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 type ExecutableTool<T = unknown> = {
   execute(input: unknown): Promise<T>;
@@ -521,7 +522,8 @@ test("list focuses RPC error marks GET questions unavailable and warns", async (
 });
 
 test("walkthrough-shaped chain rebuilds each assistant question from asked_turn_id", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(chat, /question: parseTurnQuestion\(turn\.question\)/);
   const collect = (id: string, prompt: string, status: "active" | "resolved") => ({
     id,
diff --git a/frontend/tests/rectification-range-bar-20260916.test.ts b/frontend/tests/rectification-range-bar-20260916.test.ts
index 28e2ecdf..34a7d045 100644
--- a/frontend/tests/rectification-range-bar-20260916.test.ts
+++ b/frontend/tests/rectification-range-bar-20260916.test.ts
@@ -24,12 +24,14 @@ import {
 import { parseRectificationCandidateResult } from "../src/lib/rectification-candidate-result.ts";
 import { workingRectificationTime } from "../src/lib/rectification-board-model.ts";
 import { RectificationTimeline } from "../src/components/rectification-timeline.tsx";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const read = (path: string) => readFileSync(new URL(path, import.meta.url), "utf8");
 const scale = read("../src/lib/rectification-timeline-scale.ts");
 const bar = read("../src/components/rectification-timeline.tsx");
 const board = read("../src/components/rectification-board.tsx");
-const chat = read("../src/components/rectification-agentic-chat.tsx");
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chat = rectificationChatSurface;
 const styles = read("../src/app/globals.css");
 
 const RESULT_ID = "77777777-7777-4777-8777-777777777770";
diff --git a/frontend/tests/rectification-range-delivery-20260907.test.ts b/frontend/tests/rectification-range-delivery-20260907.test.ts
index 0ecbbd85..aa1daae0 100644
--- a/frontend/tests/rectification-range-delivery-20260907.test.ts
+++ b/frontend/tests/rectification-range-delivery-20260907.test.ts
@@ -19,6 +19,7 @@ import {
 import { appendPostAdoptProspectiveWindows } from "../src/lib/rectification-agentic/v9/answer-choice.ts";
 import { RectificationRangeDelivery } from "../src/components/rectification-range-delivery.tsx";
 import type { RectificationCandidateResult } from "../src/lib/rectification-candidate-result.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const ID_A = "aaaaaaaa-aaaa-4aaa-8aaa-aaaaaaaaaaa1";
 const ID_B = "bbbbbbbb-bbbb-4bbb-8bbb-bbbbbbbbbbb2";
@@ -293,7 +294,8 @@ test("range-delivery never shows a post-card tie-break button", () => {
 
 test("the range-delivery component does not render relative support or the old two actions", () => {
   const source = readFileSync(new URL("../src/components/rectification-range-delivery.tsx", import.meta.url), "utf8");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.doesNotMatch(source, /相对支持度/);
   assert.doesNotMatch(source, /当前推荐/);
   assert.doesNotMatch(source, /采用此时间/);
@@ -311,7 +313,8 @@ test("the range-delivery component does not render relative support or the old t
 });
 
 test("chat pins the card on the offering message without a dismissed-range continue hint", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(chat, /showSelectionCards && candidateResult && message\.renderKey === selectionCardMessageKey/);
   assert.doesNotMatch(chat, /dismissedRangeResultId/);
   assert.doesNotMatch(chat, /RangeDeliveryContinueHint/);
diff --git a/frontend/tests/rectification-settled-render-split.test.ts b/frontend/tests/rectification-settled-render-split.test.ts
index 767a049a..f2e5ac64 100644
--- a/frontend/tests/rectification-settled-render-split.test.ts
+++ b/frontend/tests/rectification-settled-render-split.test.ts
@@ -18,11 +18,10 @@ import {
   homeStreamingRenderProbeSnapshot,
   resetHomeStreamingRenderProbe,
 } from "../src/lib/home-streaming-render-probe.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
-const chatSource = readFileSync(
-  new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-  "utf8",
-);
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chatSource = rectificationChatSurface;
 const entrySource = readFileSync(
   new URL("../src/components/rectification-message-entry.tsx", import.meta.url),
   "utf8",
diff --git a/frontend/tests/rectification-skipped-health-deadend-20260909.test.ts b/frontend/tests/rectification-skipped-health-deadend-20260909.test.ts
index 34bb276a..1a288637 100644
--- a/frontend/tests/rectification-skipped-health-deadend-20260909.test.ts
+++ b/frontend/tests/rectification-skipped-health-deadend-20260909.test.ts
@@ -22,6 +22,7 @@ import {
   holdoutFollowupFor,
   type MethodFollowupEvidence,
 } from "../src/lib/rectification-agentic/v9/method-followup.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const SEVEN_WITHOUT_HEALTH: MethodFollowupEvidence[] = [
   { id: "e-edu", status: "confirmed", domain: "education", datePrecision: "month", occurredFrom: "2016-09-01", occurredTo: null, eventKind: "education_start" },
@@ -141,7 +142,8 @@ test("persistNextInterviewIfIdle still narrates after duplicate_focus", async ()
 });
 
 test("unavailable gap button posts repair-exit and says 接着问", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const surface = readFileSync(new URL("../src/lib/rectification-surface-state.ts", import.meta.url), "utf8");
   const repair = readFileSync(
     new URL("../src/app/api/rectification/cases/[caseId]/repair-exit/route.ts", import.meta.url),
diff --git a/frontend/tests/rectification-spoken-answer.test.ts b/frontend/tests/rectification-spoken-answer.test.ts
index bf5a1496..79fe2ecc 100644
--- a/frontend/tests/rectification-spoken-answer.test.ts
+++ b/frontend/tests/rectification-spoken-answer.test.ts
@@ -1,11 +1,10 @@
 import assert from "node:assert/strict";
 import { readFileSync } from "node:fs";
 import test from "node:test";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
-const chat = readFileSync(
-  new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-  "utf8",
-);
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chat = rectificationChatSurface;
 const agentRun = readFileSync(
   new URL("../src/lib/rectification-agentic/v9/agent-run.ts", import.meta.url),
   "utf8",
diff --git a/frontend/tests/rectification-spoken-collect.test.ts b/frontend/tests/rectification-spoken-collect.test.ts
index d00c5572..b6f6bf7a 100644
--- a/frontend/tests/rectification-spoken-collect.test.ts
+++ b/frontend/tests/rectification-spoken-collect.test.ts
@@ -37,6 +37,7 @@ import { parseV9CaseDossier as parseDossier } from "../src/lib/rectification-age
 import { USER_COLLECT_QUESTION } from "../src/lib/rectification-agentic/user-copy.ts";
 import type { DiscriminatingEventProbe } from "../src/lib/rectification-agentic/v9/refinement-packet.ts";
 import { collectFocusCloseStatus } from "../src/lib/rectification-agentic/v9/turn-intent-classifier.ts";
+import { rectificationChatSurface, readRectificationChatFile } from "./rectification-chat-surface.ts";
 
 const RELATIONSHIP_PROMPT = USER_COLLECT_QUESTION.relationship;
 
@@ -106,7 +107,8 @@ test("skill version is 10.0.26 after the targeted-collect-cards bump", () => {
 });
 
 test("cases current_question remains the submit contract, not a visual slot", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(chat, /current_question\?: unknown/);
   assert.match(chat, /setCurrentQuestion\(nextQuestion\)/);
   assert.doesNotMatch(chat, /className="rectification-question-slot"/);
@@ -155,7 +157,8 @@ test("cases current_question remains the submit contract, not a visual slot", ()
 
 test("collect_spoken stem lives on turn.question inside the same assistant article", () => {
   // old → new → kept: slot sibling → in-bubble question → no body-text scan; refresh rebuilds from asked_turn_id
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const row = readFileSync(new URL("../src/components/chat-message-row.tsx", import.meta.url), "utf8");
   const styles = readFileSync(new URL("../src/app/globals.css", import.meta.url), "utf8");
   const agentRun = readFileSync(new URL("../src/lib/rectification-agentic/v9/agent-run.ts", import.meta.url), "utf8");
@@ -208,7 +211,8 @@ test("collect_spoken stem lives on turn.question inside the same assistant artic
 });
 
 test("missing current_question is explicit only for resumable cases", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   // Was: `const showMissingQuestion = Boolean(... caseSnapshotLoaded ... resumableCase ...
   // currentQuestion === null` plus the copy /当前没有可回答的问题，正在等待服务端更新/ and
   // /题目加载失败，请刷新/. Those were bare waiting sentences; the same inputs now feed
@@ -224,7 +228,8 @@ test("missing current_question is explicit only for resumable cases", () => {
 });
 
 test("choice options render inside the same assistant message, not a sibling slot", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const messageEntry = readFileSync(new URL("../src/components/rectification-message-entry.tsx", import.meta.url), "utf8");
   const render = chat.slice(
     chat.indexOf("{messages.map((message) => {") ,
@@ -238,10 +243,18 @@ test("choice options render inside the same assistant message, not a sibling slo
   assert.match(messageEntry, /afterAnswer/);
   assert.match(messageEntry, /actionsRef\.current\.submitChoice/);
   assert.match(messageEntry, /actionsRef\.current\.submitStop/);
-  assert.match(render, /<RectificationChoiceCard/);
-  assert.match(render, /onSelect=\{submitChoice\}/);
-  assert.match(render, /onStop=\{submitStop\}/);
+  // 原值: render（容器 map 到 savedTime 之间）含 persisted 题卡 <RectificationChoiceCard、onSelect={submitChoice}、onStop={submitStop}。
+  // 新值: render 挂 <RectificationQuestionGapNotices 并传 submitChoice / submitStop；该块里的 persisted 题卡绑 onSelect={submitChoice} / onStop={submitStop}。
+  // 原因: TASK-rectification-code-split-20260926 缺题块（含 persisted 题卡）抽成组件，位置与回调不变。
+  const gapNotices = readRectificationChatFile("../src/components/rectification-question-gap-notices.tsx");
+  assert.match(render, /<RectificationQuestionGapNotices/);
+  assert.match(render, /submitChoice=\{submitChoice\}/);
+  assert.match(render, /submitStop=\{submitStop\}/);
+  assert.match(gapNotices, /<RectificationChoiceCard/);
+  assert.match(gapNotices, /onSelect=\{submitChoice\}/);
+  assert.match(gapNotices, /onStop=\{submitStop\}/);
   assert.doesNotMatch(render, /rectification-question-slot/);
+  assert.doesNotMatch(gapNotices, /rectification-question-slot/);
   assert.doesNotMatch(render, /liveSpoken/);
   assert.doesNotMatch(render, /showLiveSpokenCollect/);
   assert.doesNotMatch(messageEntry, /rectification-question-slot/);
diff --git a/frontend/tests/rectification-step-state-20260906.test.ts b/frontend/tests/rectification-step-state-20260906.test.ts
index e9498a46..0949f490 100644
--- a/frontend/tests/rectification-step-state-20260906.test.ts
+++ b/frontend/tests/rectification-step-state-20260906.test.ts
@@ -5,6 +5,7 @@ import test from "node:test";
 import { PROBE_EXPLAIN_COPY } from "../src/lib/rectification-agentic/v9/probe-explain.ts";
 import { projectRectificationStepState, STEP_STATE_COPY } from "../src/lib/rectification-agentic/v9/step-state.ts";
 import { parseRectificationStepState } from "../src/lib/rectification-candidate-result.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 test("step state covers collect, discriminate, deliver, and post-adopt", () => {
   const collect = projectRectificationStepState({
@@ -56,7 +57,8 @@ test("step state parser rejects forbidden certainty words", () => {
 });
 
 test("chat does not render the step-state strip above the composer", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const route = readFileSync(new URL("../src/lib/rectification-agentic/v9/case-dossier-response.ts", import.meta.url), "utf8");
   assert.doesNotMatch(chat, /rectification-step-state/);
   assert.doesNotMatch(chat, /下一步：\{stepState\.next\}/);
diff --git a/frontend/tests/rectification-surface-contract.test.ts b/frontend/tests/rectification-surface-contract.test.ts
index 5e7a61af..0d9bc1bb 100644
--- a/frontend/tests/rectification-surface-contract.test.ts
+++ b/frontend/tests/rectification-surface-contract.test.ts
@@ -3,9 +3,15 @@ import { readFileSync } from "node:fs";
 import test from "node:test";
 
 import { homeSurface as page } from "./home-surface.ts";
+import { createElement } from "react";
+import { renderToStaticMarkup } from "react-dom/server";
+import { rectificationChatSurface, readRectificationChatFile } from "./rectification-chat-surface.ts";
+import { RectificationQuestionGapNotices } from "../src/components/rectification-question-gap-notices.tsx";
+import { RECTIFICATION_QUESTION_PREPARING_LABEL } from "../src/lib/rectification-surface-state.ts";
 
 const read = (relativePath: string) => readFileSync(new URL(relativePath, import.meta.url), "utf8");
-const chat = read("../src/components/rectification-agentic-chat.tsx");
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chat = rectificationChatSurface;
 const messageEntry = read("../src/components/rectification-message-entry.tsx");
 const hook = read("../src/hooks/use-rectification-surface.ts");
 const sessions = read("../src/hooks/use-session-management.ts");
@@ -127,9 +133,31 @@ test("the question gap is a live row with retries, then a reload; it never tells
   assert.match(chat, /if \(value\) setQuestionRetryAttempts\(0\);/);
   assert.doesNotMatch(chat, /useEffect\(\(\) => \{\s*if \(currentQuestion !== null/);
   // In flow: the gap is the last entry of the transcript, after the message loop, before the saved-time line.
-  const gapIndex = chat.indexOf('{questionGap === "preparing" && (');
-  assert.ok(gapIndex > chat.indexOf("{messages.map((message) => {"));
-  assert.ok(gapIndex < chat.indexOf("{savedTime && savedStatus === \"confirmed\""));
+  // 原值: chat 源码里 `{questionGap === "preparing" && (` 位于 `{messages.map` 之后、`{savedTime && savedStatus === "confirmed"` 之前。
+  // 新值: 容器里 `<RectificationQuestionGapNotices` 位于同两个锚点之间；再真渲染该块，preparing 态出 live 行和准备文案。
+  // 原因: TASK-rectification-code-split-20260926 把缺题块抽成组件，渲染位置不变；渲染断言比源码顺序更强。
+  const container = readRectificationChatFile("../src/components/rectification-agentic-chat.tsx");
+  const gapIndex = container.indexOf("<RectificationQuestionGapNotices");
+  assert.ok(gapIndex > container.indexOf("{messages.map((message) => {"));
+  assert.ok(gapIndex < container.indexOf("{savedTime && savedStatus === \"confirmed\""));
+  const preparingHtml = renderToStaticMarkup(createElement(RectificationQuestionGapNotices, {
+    view: { showStandaloneQuestion: false, questionGap: "preparing", showSelectionCards: false, verifiedIdleCopy: null },
+    currentQuestion: null,
+    choiceCard: null,
+    choiceNonce: 0,
+    busy: false,
+    readonly: false,
+    snapshotFailure: null,
+    questionRepairAttempts: 0,
+    questionRepairing: false,
+    submitChoice() {},
+    submitStop() {},
+    async refetchQuestion() {},
+    async repairQuestion() {},
+  }));
+  assert.match(preparingHtml, /class="rectification-message-wrap rectification-message-entry rectification-question-gap"/);
+  assert.match(preparingHtml, /data-status="live"/);
+  assert.ok(preparingHtml.includes(RECTIFICATION_QUESTION_PREPARING_LABEL));
   assert.match(styles, /\.rectification-question-gap \{/);
 });
 
diff --git a/frontend/tests/rectification-targeted-card-live-20260913.test.ts b/frontend/tests/rectification-targeted-card-live-20260913.test.ts
index 5cdf2aba..c34aa6df 100644
--- a/frontend/tests/rectification-targeted-card-live-20260913.test.ts
+++ b/frontend/tests/rectification-targeted-card-live-20260913.test.ts
@@ -21,6 +21,7 @@ import {
   interviewCollectWaiting,
   rectificationQuestionGapState,
 } from "../src/lib/rectification-surface-state.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const FOCUS_ID = "abababab-abab-4bab-8bab-abababababab";
 const TARGETED_PROMPT = "收入明显变过或有过大笔进出吗？";
@@ -170,7 +171,8 @@ test("a choice question without a GET card is the repair path, not collect waiti
     }),
     "unavailable",
   );
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(chat, /interviewChoiceCardUnavailable/);
   assert.match(chat, /questionSource === "unavailable" \|\| deadChoice/);
   assert.match(chat, /\/api\/rectification\/cases\/\$\{encodeURIComponent\(caseId\)\}\/repair-exit/);
diff --git a/frontend/tests/rectification-targeted-spoken-focus-recovery-20260913.test.ts b/frontend/tests/rectification-targeted-spoken-focus-recovery-20260913.test.ts
index b40b5603..3679c7c7 100644
--- a/frontend/tests/rectification-targeted-spoken-focus-recovery-20260913.test.ts
+++ b/frontend/tests/rectification-targeted-spoken-focus-recovery-20260913.test.ts
@@ -27,6 +27,7 @@ import {
 } from "../src/lib/rectification-surface-state.ts";
 import type { MethodFollowup } from "../src/lib/rectification-agentic/v9/method-followup.ts";
 import { CASE_ID, FOCUS_ID, USER_ID, fakeAccounting } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const FAMILY_PROMPT = "家里添过丁或长辈住过院吗？";
 const DATED_EVIDENCE = [
@@ -303,6 +304,7 @@ test("persistNextInterviewAfterChoice tail names persisted false", () => {
 });
 
 test("chat passes questionId into the dead-choice helper", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(chat, /interviewChoiceCardUnavailable\(\{[\s\S]*questionId: currentQuestion\?\.question_id/);
 });
diff --git a/frontend/tests/rectification-tie-break-entry-20260913.test.ts b/frontend/tests/rectification-tie-break-entry-20260913.test.ts
index 1821d2fe..2c4ec5c3 100644
--- a/frontend/tests/rectification-tie-break-entry-20260913.test.ts
+++ b/frontend/tests/rectification-tie-break-entry-20260913.test.ts
@@ -12,6 +12,7 @@ import {
   tieBreakPersonalityFollowup,
 } from "../src/lib/rectification-agentic/v9/method-followup.ts";
 import { expectedAnswerSchemaFor, stableFollowupQuestionId } from "../src/lib/rectification-agentic/v9/server-focus.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const TIMES = ["04:48", "04:53", "05:06", "05:07"] as const;
 
@@ -171,7 +172,8 @@ test("one click stamps a round schema; scoring stays tie_break without eliminati
 });
 
 test("click path does not surface 409 copy; round continue is opt-in only", () => {
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const answer = readFileSync(new URL("../src/lib/rectification-agentic/v9/answer-choice.ts", import.meta.url), "utf8");
   const panel = readFileSync(new URL("../src/lib/rectification-agentic/v9/divergence-panel.ts", import.meta.url), "utf8");
   const pool = readFileSync(new URL("../src/lib/rectification-agentic/v9/collection-question-pool.ts", import.meta.url), "utf8");
diff --git a/frontend/tests/rectification-tiebreak-card-loss-20260915.test.ts b/frontend/tests/rectification-tiebreak-card-loss-20260915.test.ts
index 66a179e2..640cbcc8 100644
--- a/frontend/tests/rectification-tiebreak-card-loss-20260915.test.ts
+++ b/frontend/tests/rectification-tiebreak-card-loss-20260915.test.ts
@@ -7,11 +7,12 @@ import { interviewChoiceCardUnavailable } from "../src/lib/rectification-surface
 import { MACHINE_VOICE_LEXICON } from "../src/lib/rectification-agentic/v9/agent-voice-lexicon.ts";
 import { validateAdoptNarration, type AdoptDeliveryFacts } from "../src/lib/rectification-agentic/v9/adopt-narration.ts";
 import { RECTIFICATION_USER_COPY } from "../src/lib/rectification-agentic/user-copy.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
+import { deriveRectificationChatView } from "../src/lib/rectification-chat-view.ts";
+import { chatViewInput, offerableCandidateResult, settledAssistant } from "./rectification-chat-run-fixtures.ts";
 
-const chat = readFileSync(
-  new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-  "utf8",
-);
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chat = rectificationChatSurface;
 const card = readFileSync(
   new URL("../src/components/rectification-range-delivery.tsx", import.meta.url),
   "utf8",
@@ -48,10 +49,33 @@ test("the delivery card no longer renders a post-card tie-break entry", () => {
   assert.doesNotMatch(css, /rectification-range-delivery__tie-break/);
   assert.match(chat, /adoptLocked=\{liveInterviewBlockingAdopt\}/);
   assert.match(chat, /liveInterviewBlockingAdopt/);
-  assert.doesNotMatch(
-    chat.slice(chat.indexOf("const showSelectionCards"), chat.indexOf("const showReadonlyRange")),
-    /interviewQuestionBlocksAdoptOffer/,
-  );
+  // 原值: 从 chat 源码切 `const showSelectionCards` 到 `const showReadonlyRange`，断言不含 interviewQuestionBlocksAdoptOffer。
+  // 新值: 调用 deriveRectificationChatView：最新回复上挂着一道没答的采集题时，交付卡照常出（showSelectionCards
+  //       不变），只把采用锁上（liveInterviewBlockingAdopt）。
+  // 原因: TASK-rectification-code-split-20260926 派生逻辑原样搬进纯函数 rectification-chat-view.ts。
+  const result = offerableCandidateResult();
+  const openCollect = {
+    focus_id: "aaaaaaaa-aaaa-4aaa-8aaa-aaaaaaaaaaa1",
+    question_id: "collect:career",
+    kind: "collect_spoken" as const,
+    prompt: "先说你最容易想起的一两件，年月大概就行",
+    options: null,
+    status: "active",
+    answer_option: null,
+    probe_id: null,
+  };
+  const quiet = deriveRectificationChatView(chatViewInput({
+    messages: [settledAssistant("offer-1")],
+    candidateResult: result,
+  }));
+  const withOpenQuestion = deriveRectificationChatView(chatViewInput({
+    messages: [settledAssistant("offer-1", { question: openCollect })],
+    candidateResult: result,
+  }));
+  assert.equal(quiet.showSelectionCards, true);
+  assert.equal(quiet.liveInterviewBlockingAdopt, false);
+  assert.equal(withOpenQuestion.showSelectionCards, true);
+  assert.equal(withOpenQuestion.liveInterviewBlockingAdopt, true);
 });
 
 test("tie-break availability reuses the choice-card renderability gate", () => {
diff --git a/frontend/tests/rectification-timeline-20260909.test.ts b/frontend/tests/rectification-timeline-20260909.test.ts
index 4a231739..6e29091d 100644
--- a/frontend/tests/rectification-timeline-20260909.test.ts
+++ b/frontend/tests/rectification-timeline-20260909.test.ts
@@ -10,11 +10,16 @@ import {
   timelineDurationLabel,
   timelineTickStepMinutes,
 } from "../src/lib/rectification-timeline-scale.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
+import { deriveRectificationChatView } from "../src/lib/rectification-chat-view.ts";
+import { workingRectificationTime } from "../src/lib/rectification-board-model.ts";
+import { chatViewInput, offerableCandidateResult } from "./rectification-chat-run-fixtures.ts";
 
 const read = (relativePath: string) => readFileSync(new URL(relativePath, import.meta.url), "utf8");
 const component = read("../src/components/rectification-timeline.tsx");
 const scale = read("../src/lib/rectification-timeline-scale.ts");
-const chat = read("../src/components/rectification-agentic-chat.tsx");
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chat = rectificationChatSurface;
 const anchor = read("../src/hooks/use-conversation-scroll-anchor.ts");
 const styles = read("../src/app/globals.css");
 
@@ -278,12 +283,51 @@ test("eliminated inference minutes stay as hollow dots and keep stable keys", ()
 });
 
 test("timeline chat wiring reads parsed inferenceMarks and never the raw receipt", () => {
-  const timelineBlock = chat.slice(
-    chat.indexOf("const timelineView = buildRectificationTimeline"),
-    chat.indexOf("const persistedOfferKey"),
-  );
-  assert.match(timelineBlock, /inferenceMarks:\s*candidateResult\?\.inferenceMarks/);
-  assert.doesNotMatch(timelineBlock, /decisionReceipt|inference_state/);
+  // 原值: 从 chat 源码切 `const timelineView = buildRectificationTimeline` 到 `const persistedOfferKey`，
+  //       匹配 `inferenceMarks: candidateResult?.inferenceMarks`，且不含 decisionReceipt / inference_state。
+  // 新值: 调用 deriveRectificationChatView：时间轴刻度来自解析后的 inferenceMarks（与直接用它们建轴一致、
+  //       与只用候选分钟建轴不同）；只改 decisionReceipt 里的 inference_state，时间轴不变。
+  // 原因: TASK-rectification-code-split-20260926 时间轴派生原样搬进纯函数 rectification-chat-view.ts。
+  const marks = [
+    { time: "04:50", eliminated: true },
+    { time: "04:53", eliminated: false },
+    { time: "04:57", eliminated: true },
+  ];
+  const base = offerableCandidateResult();
+  const withMarks = { ...base, inferenceMarks: marks };
+  const input = chatViewInput({
+    candidateResult: withMarks,
+    searchWindow: ["04:45", "05:15"],
+    caseStage: "minute",
+  });
+  const view = deriveRectificationChatView(input);
+  assert.ok(view.timelineView);
+  assert.equal(view.timelineView.marks.length, 3);
+  const direct = buildRectificationTimeline({
+    searchWindow: ["04:45", "05:15"],
+    credibleRange: withMarks.credibleRange ?? null,
+    candidateTimes: withMarks.candidates.map((candidate) => candidate.time),
+    inferenceMarks: marks,
+    stage: "minute",
+    workingTime: workingRectificationTime(withMarks),
+    workingAdopted: false,
+    answeredProbeCount: withMarks.answeredProbeCount ?? null,
+    datedEventCount: withMarks.rangeDelivery?.event_count ?? null,
+  });
+  assert.deepEqual(view.timelineView, direct);
+  const candidatesOnly = deriveRectificationChatView({ ...input, candidateResult: { ...base, inferenceMarks: [] } });
+  assert.notDeepEqual(candidatesOnly.timelineView?.marks, view.timelineView.marks);
+  const receiptChanged = deriveRectificationChatView({
+    ...input,
+    candidateResult: {
+      ...withMarks,
+      decisionReceipt: {
+        ...(withMarks.decisionReceipt ?? {}),
+        inference_state: { candidates: [{ time: "05:10", eliminated: false }] },
+      } as typeof withMarks.decisionReceipt,
+    },
+  });
+  assert.deepEqual(receiptChanged.timelineView, view.timelineView);
 });
 
 test("parsed inference_state marks reach the timeline even when engine candidates are only the active minutes", () => {
diff --git a/frontend/tests/rectification-timeline-adapter.test.ts b/frontend/tests/rectification-timeline-adapter.test.ts
index 67beb06e..b6dcaccf 100644
--- a/frontend/tests/rectification-timeline-adapter.test.ts
+++ b/frontend/tests/rectification-timeline-adapter.test.ts
@@ -14,9 +14,11 @@ import {
 } from "../src/lib/rectification-timeline-adapter.ts";
 import { RECTIFICATION_ANALYZING_LIVE_LABEL } from "../src/lib/rectification-activity-labels.ts";
 import { PUBLIC_RECTIFICATION_METHODS } from "../src/lib/rectification-agentic/v9/public-receipt.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const read = (path: string) => readFileSync(new URL(`../${path}`, import.meta.url), "utf8");
-const chatSource = read("src/components/rectification-agentic-chat.tsx");
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chatSource = rectificationChatSurface;
 const entrySource = read("src/components/rectification-message-entry.tsx");
 const rowSource = read("src/components/chat-message-row.tsx");
 const activitySource = read("src/components/agent-activity-status.tsx");
diff --git a/frontend/tests/rectification-unwritten-evidence.test.ts b/frontend/tests/rectification-unwritten-evidence.test.ts
index b07cf294..92aadaf2 100644
--- a/frontend/tests/rectification-unwritten-evidence.test.ts
+++ b/frontend/tests/rectification-unwritten-evidence.test.ts
@@ -30,6 +30,7 @@ import {
   fakeAccounting,
   receiptHandlers,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const REJECTION = {
   error: true,
@@ -353,10 +354,8 @@ test("rejected batch tool-result is failed in the runner terminal status", async
 });
 
 test("chat live question only reads the last settled assistant message", () => {
-  const chat = readFileSync(
-    new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-    "utf8",
-  );
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   // 原值: messages.some((message) => role/state/question/focus_id)
   // 新值: latestSettledAssistant 且 question.focus_id 对应当前焦点
   // 原因: BUG-635 旧消息上的同 focus_id 不再算仍在显示
diff --git a/frontend/tests/rectification-v10-focus-receipt-consistency.test.ts b/frontend/tests/rectification-v10-focus-receipt-consistency.test.ts
index 37048182..68fc025e 100644
--- a/frontend/tests/rectification-v10-focus-receipt-consistency.test.ts
+++ b/frontend/tests/rectification-v10-focus-receipt-consistency.test.ts
@@ -21,6 +21,7 @@ import {
   activeFocusFixture,
   fakeAccounting,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const migrationFilename = "20260815010000_rectification_focus_receipt_consistency.sql";
 const migration = readFileSync(
@@ -148,10 +149,8 @@ const caseRoute = readFileSync(
   new URL("../src/lib/rectification-agentic/v9/case-dossier-response.ts", import.meta.url),
   "utf8",
 );
-const chat = readFileSync(
-  new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url),
-  "utf8",
-);
+// 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+const chat = rectificationChatSurface;
 
 test("refresh projection rebuilds the same activity receipt from persisted terminal states", () => {
   assert.match(caseRoute, /tool_activities: receipt\.toolActivities\.map/);
diff --git a/frontend/tests/rectification-v9-contracts.test.ts b/frontend/tests/rectification-v9-contracts.test.ts
index e614d118..4221707e 100644
--- a/frontend/tests/rectification-v9-contracts.test.ts
+++ b/frontend/tests/rectification-v9-contracts.test.ts
@@ -43,6 +43,7 @@ import {
   openRectificationCaseRequestSchema,
   shouldStartOpening,
 } from "../src/lib/rectification-agentic/v9/open-request.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const skillDirectory = fileURLToPath(
   new URL("../../skills/jyotish-birth-time-rectification", import.meta.url),
@@ -254,7 +255,8 @@ test("case snapshot includes step_state without a composer strip", () => {
   // 新值: 断言读 case-dossier-response.ts
   // 原因: Next App Router 不允许 route.ts 导出非 HTTP handler。
   const route = readFileSync(new URL("../src/lib/rectification-agentic/v9/case-dossier-response.ts", import.meta.url), "utf8");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(route, /step_state: stepStateFromCaseDossier\(dossier\)/);
   assert.doesNotMatch(chat, /rectification-step-state/);
 });
diff --git a/frontend/tests/rectification-varga-style-copy.test.ts b/frontend/tests/rectification-varga-style-copy.test.ts
index 8cf668d9..b4528701 100644
--- a/frontend/tests/rectification-varga-style-copy.test.ts
+++ b/frontend/tests/rectification-varga-style-copy.test.ts
@@ -19,6 +19,7 @@ import {
   d9StyleLabel,
   d10StyleLabel,
 } from "../src/lib/rectification-agentic/v9/varga-type-tables.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const SIGNS = [
   "白羊座", "金牛座", "双子座", "巨蟹座", "狮子座", "处女座",
@@ -338,7 +339,8 @@ test("remaining D9/D10 packets use userChoice labels and long-term questions", (
 test("embedded choice cards hide the duplicate legend; standalone cards keep the stem visible", () => {
   const globals = readFileSync(new URL("../src/app/globals.css", import.meta.url), "utf8");
   const card = readFileSync(new URL("../src/components/rectification-choice-card.tsx", import.meta.url), "utf8");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   const whyRule = globals.match(/\.rectification-choice-why-user \{[^}]+\}/)?.[0] ?? "";
   const legendRule = globals.match(
     /\.rectification-choice-card \.birth-time-choice-question legend \{[^}]+\}/,
diff --git a/frontend/tests/rectification-walkthrough-polish.test.ts b/frontend/tests/rectification-walkthrough-polish.test.ts
index 8467ae13..cc23c0c2 100644
--- a/frontend/tests/rectification-walkthrough-polish.test.ts
+++ b/frontend/tests/rectification-walkthrough-polish.test.ts
@@ -35,6 +35,7 @@ import {
   USER_ID,
   fakeAccounting,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const D9_QUESTION = "亲密关系里，你更接近哪一种相处方式？";
 
@@ -415,7 +416,8 @@ test("unwired D9 persist skips instead of opening a spoken collect", async () =>
 
 test("agent instructions do not assert that the next question is already on screen", () => {
   const agent = readFileSync(new URL("../src/mastra/agentic-rectification.ts", import.meta.url), "utf8");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.match(agent, /正文不得断言界面当前状态/);
   // 旧：用「接下来我们继续」垫句 → 新：题干作为同一条消息下一段出现，不再垫过渡句
   // 原因：BUG-606 每轮一句，开场/证据轮不再写「接下来我们继续」
diff --git a/frontend/tests/rectification-year-focus-overlay-20260916.test.ts b/frontend/tests/rectification-year-focus-overlay-20260916.test.ts
index 14473afc..931fc7db 100644
--- a/frontend/tests/rectification-year-focus-overlay-20260916.test.ts
+++ b/frontend/tests/rectification-year-focus-overlay-20260916.test.ts
@@ -24,6 +24,7 @@ import {
   USER_ID,
   fakeAccounting,
 } from "./rectification-v9-test-support.ts";
+import { rectificationChatSurface } from "./rectification-chat-surface.ts";
 
 const YEAR_Q = "collect:targeted:health_pressure:year";
 const SERVER_PROMPT = TARGETED_YEAR_PROMPT;
@@ -52,7 +53,8 @@ test("year-stage questions are typed collect, not an entry card (T0)", () => {
   assert.equal(isYearStageQuestionId(YEAR_Q), true);
   assert.equal(isYearStageQuestionId("collect:targeted:health_pressure"), false);
   assert.equal(TARGETED_COLLECT_OPTION_A, "有，我来说");
-  const chat = readFileSync(new URL("../src/components/rectification-agentic-chat.tsx", import.meta.url), "utf8");
+  // 原值: 读 rectification-agentic-chat.tsx 单文件。新值: rectificationChatSurface（容器 + 拆出的 hook / 参数函数 / 块，见 rectification-chat-surface.ts）。原因: TASK-rectification-code-split-20260926 只搬不改，整文件断言跟着代码走；切片断言另行改为调用函数。
+  const chat = rectificationChatSurface;
   assert.doesNotMatch(chat, /EventDateEntryCard|event_date_entry/);
   const followup = yearFollowup("health_pressure");
   const schema = collectFocusSchema(followup);