feat(rectification): remove the rectification regenerate button and endpoint (BUG-1056)

T2 of TASK-rectification-grounding-20260927 (product decision P1).
The rectification 「重试（重新生成）」 was a blind agent.generate rewrite that
persisted unchecked text (invented range / fit rate reproduced). Removed:
the regenerate route, regenerate-turn.ts, the regeneration agent and its
read-only tool set, the client regenerate action/state and the
regenerating/canRegenerate props. ChatMessageActions renders the regenerate
button only when onRegenerate is passed; ordinary consultation is unchanged.
The DB function regenerate_agentic_rectification_turn is kept (AGENTS §7.6,
retire in a later round). DESIGN.md / VOICE.md updated; source-contract
tests follow with 原值/新值/原因 notes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017eEAG8HD3mm8gsKXgk8uU8

frontend/src/components/chat-message-actions.tsx

@@ -21,10 +21,11 @@ export function ChatMessageActions({
 }: Readonly<{
   feedback?: ChatMessageFeedback;
   copied?: boolean;
-  canRegenerate: boolean;
+  /** Without `onRegenerate` the regenerate button is not rendered (rectification, BUG-1056). */
+  canRegenerate?: boolean;
   onFeedback: (value: ChatMessageFeedback) => void;
   onCopy: () => void;
-  onRegenerate: () => void;
+  onRegenerate?: () => void;
 }>) {
   return (
     <div className="message-actions" aria-label="Agent 回答操作">
@@ -51,15 +52,17 @@ export function ChatMessageActions({
       <button aria-label="复制回答" title="复制" type="button" onClick={onCopy}>
         {copied ? <Check aria-hidden="true" /> : <Copy aria-hidden="true" />}
       </button>
-      <button
-        aria-label="重新生成回答"
-        disabled={!canRegenerate}
-        title={canRegenerate ? "重新生成" : "只能重新生成最近一条回答"}
-        type="button"
-        onClick={onRegenerate}
-      >
-        <RotateCcw aria-hidden="true" />
-      </button>
+      {onRegenerate && (
+        <button
+          aria-label="重新生成回答"
+          disabled={!canRegenerate}
+          title={canRegenerate ? "重新生成" : "只能重新生成最近一条回答"}
+          type="button"
+          onClick={onRegenerate}
+        >
+          <RotateCcw aria-hidden="true" />
+        </button>
+      )}
     </div>
   );
 }

frontend/src/components/rectification-agentic-chat.tsx

@@ -58,10 +58,7 @@ import {
   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 { copyRectificationMessage } from "@/lib/rectification-chat-message-actions";
 import {
   refetchRectificationQuestion,
   repairRectificationQuestion,
@@ -177,13 +174,11 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
   const [acceptingCandidateId, setAcceptingCandidateId] = useState<string | null>(null);
   const [feedback, setFeedback] = useState<Record<string, "up" | "down" | undefined>>({});
   const [copiedMessageKey, setCopiedMessageKey] = useState<string | null>(null);
-  const [regeneratingMessageKey, setRegeneratingMessageKey] = useState<string | null>(null);
   const [choiceNonce, setChoiceNonce] = useState(0);
   const messageActionsRef = useRef<RectificationMessageActions>({
     submitChoice() {},
     submitStop() {},
     copyMessage() {},
-    regenerateMessage() {},
     onFeedback() {},
   });
   const conversation = useRef<HTMLElement>(null);
@@ -390,23 +385,10 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
     await copyRectificationMessage({ setCopiedMessageKey }, message);
   }
 
-  async function regenerateMessage(message: RenderMessage) {
-    await regenerateRectificationMessage({
-      caseId,
-      sessionId,
-      busy,
-      readonly,
-      regeneratingMessageKey,
-      setError,
-      setMessages,
-      setRegeneratingMessageKey,
-    }, message);
-  }
-
   async function submit(event: React.FormEvent) {
     event.preventDefault();
     if (readonly) return;
-    if (busy || regeneratingMessageKey) {
+    if (busy) {
       if (queued.enqueue(draft)) setDraft("");
       return;
     }
@@ -416,7 +398,6 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
   }
 
   const {
-    latestRegeneratableKey,
     latestSettledAssistant,
     showLiveChoiceCard,
     timelineView,
@@ -436,7 +417,6 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
     messages,
     busy,
     readonly,
-    regeneratingMessageKey,
     shouldStartOpening,
     openingRequested,
     acceptingCandidateId,
@@ -529,7 +509,6 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
       submitChoice,
       submitStop,
       copyMessage,
-      regenerateMessage,
       onFeedback(renderKey, requested) {
         setFeedback((current) => ({
           ...current,
@@ -564,7 +543,7 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
           ref={conversation}
           className="conversation is-rectification"
           aria-label="生时校正对话"
-          aria-busy={busy || regeneratingMessageKey !== null}
+          aria-busy={busy}
         >
           <div className="message-list">
           {resultNotice && <p role="status" className="rectification-pending-note">{resultNotice}</p>}
@@ -585,11 +564,6 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
           {messages.map((message) => {
             // D3: the same message with the persisted question placed on it.
             const entryMessage = placedByKey?.get(message.renderKey) ?? message;
-            const regenerating = regeneratingMessageKey === message.renderKey;
-            const canRegenerate = message.renderKey === latestRegeneratableKey
-              && !busy
-              && !readonly
-              && regeneratingMessageKey === null;
             return (
               <div
                 key={message.renderKey}
@@ -599,10 +573,8 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
                   message={entryMessage}
                   busy={busy}
                   readonly={readonly}
-                  regenerating={regenerating}
-                  canRegenerate={canRegenerate}
                   currentQuestionFocusId={currentQuestion?.focus_id ?? null}
-                  interactive={!busy && !readonly && regeneratingMessageKey === null}
+                  interactive={!busy && !readonly}
                   liveChoiceCard={choiceCard}
                   choiceNonce={choiceNonce}
                   savedTime={savedTime}
@@ -615,7 +587,7 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
                     <RectificationRangeDelivery
                       result={candidateResult}
                       acceptingCandidateId={acceptingCandidateId}
-                      readonly={readonly || regeneratingMessageKey !== null || (busy && !acceptingCandidateId)}
+                      readonly={readonly || (busy && !acceptingCandidateId)}
                       onAccept={(candidateId) => void acceptCandidate(candidateId)}
                       adoptLocked={liveInterviewBlockingAdopt}
                     />

frontend/src/components/rectification-message-entry.tsx

@@ -8,7 +8,7 @@ import {
 } from "@/components/chat-message-actions";
 import { ChatMessageRow } from "@/components/chat-message-row";
 import { RectificationChoiceCard } from "@/components/rectification-choice-card";
-import { emptyActivityTrace, type AgentActivityTraceItem } from "@/lib/agent-activity-trace";
+import type { AgentActivityTraceItem } from "@/lib/agent-activity-trace";
 import type { ChatMessageView } from "@/lib/chat-message-view";
 import {
   noteSettledRowRender,
@@ -48,7 +48,6 @@ export type RectificationMessageActions = Readonly<{
   submitChoice: (key: ChoiceKey) => void;
   submitStop: () => void;
   copyMessage: (message: RenderMessage) => void;
-  regenerateMessage: (message: RenderMessage) => void;
   onFeedback: (renderKey: string, requested: ChatMessageFeedback) => void;
 }>;
 
@@ -56,8 +55,6 @@ export type RectificationMessageEntryProps = Readonly<{
   message: RenderMessage;
   busy: boolean;
   readonly: boolean;
-  regenerating: boolean;
-  canRegenerate: boolean;
   currentQuestionFocusId: string | null;
   interactive: boolean;
   liveChoiceCard: ChoiceCardModel | null;
@@ -102,8 +99,6 @@ export function choiceCardFromQuestion(
 function RectificationMessageEntryView({
   message,
   busy,
-  regenerating,
-  canRegenerate,
   currentQuestionFocusId,
   interactive,
   liveChoiceCard,
@@ -117,30 +112,19 @@ function RectificationMessageEntryView({
     && message.state === "settled"
     && !message.failed
     && Boolean(message.text);
-  const displayedMessage: RenderMessage = regenerating
-    ? {
-      ...message,
-      text: "",
-      thinkingText: undefined,
-      state: "thinking" as const,
-      activity: undefined,
-      activityTrace: emptyActivityTrace(),
-      completedReceipt: undefined,
-      timeline: [],
-    }
-    : {
-      ...message,
-      timeline: rectificationTimelineRows({
-        trace: message.activityTrace,
-        receipt: message.completedReceipt,
-        activity: message.activity,
-        settled: message.state === "settled",
-      }),
-    };
+  const displayedMessage: RenderMessage = {
+    ...message,
+    timeline: rectificationTimelineRows({
+      trace: message.activityTrace,
+      receipt: message.completedReceipt,
+      activity: message.activity,
+      settled: message.state === "settled",
+    }),
+  };
   const vargaSentence = !message.failed
     ? vargaSentenceFromMethods(message.completedReceipt?.methods)
     : null;
-  const question = regenerating ? undefined : message.question;
+  const question = message.question;
   const liveQuestion = Boolean(
     question
     && currentQuestionFocusId === question.focus_id
@@ -193,7 +177,7 @@ function RectificationMessageEntryView({
 
   return (
     <>
-      {(!message.failed || Boolean(displayedMessage.text) || regenerating) && (
+      {(!message.failed || Boolean(displayedMessage.text)) && (
         <ChatMessageRow
           message={displayedMessage}
           showActivity={displayedMessage.state !== "settled"}
@@ -202,14 +186,13 @@ function RectificationMessageEntryView({
           stoppedNotice={message.stopped ? RECTIFICATION_STOPPED_NOTICE : undefined}
         />
       )}
-      {showActions && !regenerating && (
+      {/* BUG-1056: copy and feedback only; the rectification reply has no rewrite action. */}
+      {showActions && (
         <ChatMessageActions
           feedback={feedback}
           copied={copied}
-          canRegenerate={canRegenerate}
           onFeedback={(requested) => actionsRef.current.onFeedback(message.renderKey, requested)}
           onCopy={() => void actionsRef.current.copyMessage(message)}
-          onRegenerate={() => void actionsRef.current.regenerateMessage(message)}
         />
       )}
     </>
@@ -219,24 +202,20 @@ function RectificationMessageEntryView({
 export const RectificationMessageEntry = memo(function RectificationMessageEntry(
   props: RectificationMessageEntryProps,
 ) {
-  if (props.regenerating || props.message.state !== "settled") noteStreamingRowRender();
+  if (props.message.state !== "settled") noteStreamingRowRender();
   else noteSettledRowRender();
   return <RectificationMessageEntryView {...props} />;
 });
 
 export function UnsplitRectificationMessageList({
   messages,
-  latestRegeneratableKey,
   copiedMessageKey,
   feedbackByKey,
-  regeneratingMessageKey,
   ...shared
-}: Omit<RectificationMessageEntryProps, "message" | "regenerating" | "canRegenerate" | "copied" | "feedback"> & {
+}: Omit<RectificationMessageEntryProps, "message" | "copied" | "feedback"> & {
   messages: readonly RenderMessage[];
-  latestRegeneratableKey?: string;
   copiedMessageKey: string | null;
   feedbackByKey: Readonly<Record<string, ChatMessageFeedback | undefined>>;
-  regeneratingMessageKey: string | null;
 }) {
   noteUnsplitListRender();
   return (
@@ -249,8 +228,6 @@ export function UnsplitRectificationMessageList({
             key={message.renderKey}
             {...shared}
             message={message}
-            regenerating={regeneratingMessageKey === message.renderKey}
-            canRegenerate={message.renderKey === latestRegeneratableKey && shared.interactive}
             copied={copiedMessageKey === message.renderKey}
             feedback={feedbackByKey[message.renderKey]}
           />