fix(ui): 加回 agent 头像，范围带调深到看得见

产品真机走查：

1. agent 头像加回来（推翻 R3 的 D7）。R3 删它的理由是「一屏几十条时是重复度
   最高的元素」，但没有它助手那一轮就没有视觉归属——生时校正面尤其明显，
   旁白、题干、选项全是平铺文字。--assistant-content-inset 随之回到
   「32px 头像 + 间隙」，追问 chip 与运行时间轴重新对齐正文。

2. 时间范围带用的是 --color-action-soft，那是给文字底色用的浅色调，
   画在画布上几乎看不见——而它是整条轴上唯一必须一眼看到的标记。
   改成 color-mix(--color-action-strong 32%, --color-canvas)。

测试 3369，fail 仍 31 且与基线逐条一致；四个路由标记不变。

未修：生时校正面顶部溢出。工作区在栅格里、没有脱离定位，
chat-panel.is-rectification 仍是 46px + 1fr 两行，从代码上看不出
46px 顶栏为什么会消失，待产品确认截图是否裁切。

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0193vBv6w5MV2cifdTUu9H5P

frontend/src/app/globals.css

@@ -357,7 +357,7 @@ button:disabled { cursor: default; opacity: .45; }
 .birth-time-assessment-progress > span { font-size: var(--type-body-sm); line-height: 1.55; text-wrap: pretty; word-break: auto-phrase; }
 .onboarding-inline-error { margin-left: 0; }
 
-.message-assistant { align-items: flex-start; justify-content: flex-start; }
+.message-assistant { align-items: flex-start; justify-content: flex-start; gap: var(--space-3); }
 .message-user { justify-content: flex-end; }
 .message-user .message-content { display: flex; flex-direction: column; align-items: flex-end; }
 .message-assistant .message-content { width: auto; max-width: none; flex: 1; }
@@ -1055,10 +1055,9 @@ button:disabled { cursor: default; opacity: .45; }
 
 .rectification-entry-error { grid-column: 1 / -1; margin: 0; }
 .message-list {
-  /* The assistant reply starts at the column edge now; the 32px avatar and
-     its gap are gone, so anything that used to line up beside it (follow-up
-     chips, the run timeline) lines up with the text itself. */
-  --assistant-content-inset: 0px;
+  /* Follow-up chips and the run timeline line up with the assistant's text,
+     which starts past the avatar and its gap. */
+  --assistant-content-inset: calc(32px + var(--space-3));
   margin: 0 auto;
   width: min(900px, 100%);
   padding: var(--space-8) var(--space-8) var(--space-16);
@@ -1071,6 +1070,8 @@ button:disabled { cursor: default; opacity: .45; }
   color: var(--color-ink-secondary);
 }
 .message { display: flex; padding: var(--space-2) 0; }
+/* Restored after real-device review; see chat-message-row.tsx for why. */
+.agent-avatar { width: 32px; height: 32px; display: block; flex: 0 0 32px; margin-top: var(--space-2); border-radius: 50%; background: var(--color-canvas) url("/jyotish-logo.png") center / contain no-repeat; box-shadow: 0 0 0 1px var(--ring-hairline); }
 .message-content { min-width: 0; max-width: min(80%, 680px); }
 .message-bubble { overflow: hidden; border: 0; padding: var(--space-3) var(--space-4); border-radius: var(--radius-lg); background: var(--color-canvas-muted); }
 .message-assistant .message-bubble { border-radius: 0; background: transparent; padding: var(--space-3) 0; }
@@ -2240,6 +2241,14 @@ button.nav-rail-identity:hover { background: var(--sidebar-accent); }
   gap: var(--space-4);
 }
 
+.conversation:not(.is-empty):not(.is-rectification) .message-assistant .agent-avatar {
+  width: 30px;
+  height: 30px;
+  flex-basis: 30px;
+  margin-top: 2px;
+  box-shadow: 0 0 0 1px color-mix(in srgb, var(--color-border) 82%, transparent);
+}
+
 
 .conversation:not(.is-empty):not(.is-rectification) .message-assistant .message-bubble {
   padding: 0 0 var(--space-2);
@@ -2531,9 +2540,9 @@ button.nav-rail-identity:hover { background: var(--sidebar-accent); }
    The pending state keeps the same box for the same reason. */
 .rectification-workspace__chat {
   --rectification-timeline-height: 64px;
-  /* Same token as `.message-list`. The bar sits outside the transcript, so it
-     cannot inherit that custom property from there. */
-  --assistant-content-inset: 0px;
+  /* Same token as `.message-list`: avatar 32px + gap. The bar sits outside the
+     transcript, so it cannot inherit that custom property from there. */
+  --assistant-content-inset: calc(32px + var(--space-3));
 }
 .rectification-timeline {
   height: var(--rectification-timeline-height);
@@ -2614,7 +2623,10 @@ button.nav-rail-identity:hover { background: var(--sidebar-accent); }
   width: 100%;
   height: 11px;
   border-radius: 2px;
-  background: var(--color-action-soft);
+  /* Was --color-action-soft, which is a tint for text backgrounds: on the
+     canvas it left the range band all but invisible. This is the one mark
+     that has to read at a glance. */
+  background: color-mix(in srgb, var(--color-action-strong) 32%, var(--color-canvas));
   transform-origin: left center;
   will-change: transform;
   transition: transform 420ms cubic-bezier(.32, .72, .24, 1);

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

@@ -31,6 +31,14 @@ function motionPreferred() {
 
 if (motionPreferred()) prefetchOnIdle(loadGsap);
 
+/* Restored after real-device review: R3 removed it on the grounds that it was
+   the most repeated element in a long transcript, but without it the assistant
+   turn has no visual owner — in the rectification surface especially, where
+   narration, a question and its options all stack as plain text. */
+export function AgentAvatar() {
+  return <span className="agent-avatar" aria-hidden="true" />;
+}
+
 export const ChatMessageRow = memo(function ChatMessageRow({
   message,
   showActivity = message.state !== "settled",
@@ -123,6 +131,7 @@ export const ChatMessageRow = memo(function ChatMessageRow({
       className={`message message-${message.role}`}
       aria-label={message.role === "assistant" ? assistantLabel : "你"}
     >
+      {message.role === "assistant" && <AgentAvatar />}
       <div className="message-content">
         <div className="message-bubble">
           {message.role === "assistant" ? (

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

@@ -1,6 +1,7 @@
 "use client";
 
 import { ChatMessageContent } from "@/components/chat-message-content";
+import { AgentAvatar } from "@/components/chat-message-row";
 import { protectOnboardingPhrases } from "@/lib/onboarding-copy";
 import type { Message } from "@/lib/home-types";
 
@@ -9,6 +10,7 @@ export function OnboardingChatMessage({ role, text, streaming = false, length =
   const protectedVisibleText = protectOnboardingPhrases(visibleText);
   return (
     <article className={`message message-${role} onboarding-message${phraseSafe ? " is-phrase-safe" : ""}`} aria-label={role === "assistant" ? "Jyotisha" : "你"}>
+      {role === "assistant" && <AgentAvatar />}
       <div className="message-content">
         <div className="message-bubble">
           {role === "assistant" ? (

frontend/tests/rectification-agentic-entry.test.ts

@@ -487,7 +487,7 @@ test("candidate state renders from the snapshot API and never from sentinels", (
   assert.match(styles, /\.rectification-snapshot \{/);
   assert.match(styles, /\.rectification-house-table \{[^}]*border:\s*1px solid var\(--color-border\)/);
   assert.match(styles, /\.rectification-house-table \{[^}]*background:\s*var\(--color-canvas-soft\)/);
-  assert.match(styles, /\.message-list \{[\s\S]*?--assistant-content-inset: 0px/);
+  assert.match(styles, /\.message-list \{[\s\S]*?--assistant-content-inset: calc\(32px \+ var\(--space-3\)\)/);
   assert.match(styles, /\.rectification-message-wrap \.rectification-candidates \{[\s\S]*width: calc\(100% - var\(--assistant-content-inset\)\)/);
   assert.match(styles, /\.rectification-message-wrap \.rectification-candidates \{[\s\S]*margin-inline-start: var\(--assistant-content-inset\)/);
   assert.match(styles, /\.rectification-workspace \{[\s\S]*grid-template-columns: minmax\(0, 1fr\) minmax\(18rem, 22\.5rem\)/);

frontend/tests/rectification-timeline-20260909.test.ts

@@ -408,7 +408,10 @@ test("the chat grid has three rows and the timeline row is a fixed height", () =
   // stick-to-bottom, since it sits outside the observed scroll container.
   assert.doesNotMatch(barRule, /min-height|height:\s*auto/);
   // Inner padding matches the assistant column, not the chat-panel edge.
-  assert.match(chatRule, /--assistant-content-inset: 0px;/);
+  // 原值 `0px` / 新值 `calc(32px + var(--space-3))`
+  // / 原因：产品在真机走查后要求把 agent 头像加回来（推翻 R3 的 D7）；
+  // 这条缩进跟着头像走，时间轴仍与助手正文左边界对齐，规则本身没变。
+  assert.match(chatRule, /--assistant-content-inset: calc\(32px \+ var\(--space-3\)\);/);
   assert.match(barRule, /padding: 0 calc\(var\(--space-8\) \+ var\(--assistant-content-inset\)\);/);
 });