Show persistent timestamps for operation and teacher messages

src/lib/message-timestamp.ts

@@ -0,0 +1,18 @@
+import { messageTimestamp } from '../../shared/message-timestamp';
+
+export function formatMessageTimestamp(value: unknown, now = new Date()) {
+  const timestamp = messageTimestamp(value);
+  if (timestamp === undefined) return undefined;
+  const date = new Date(timestamp);
+  const pad = (part: number) => String(part).padStart(2, '0');
+  const time = `${pad(date.getHours())}:${pad(date.getMinutes())}`;
+  const sameYear = date.getFullYear() === now.getFullYear();
+  const today = sameYear && date.getMonth() === now.getMonth() && date.getDate() === now.getDate();
+  const day = `${date.getMonth() + 1}月${date.getDate()}日`;
+  return {
+    iso: date.toISOString(),
+    short: today ? time : `${sameYear ? '' : `${date.getFullYear()}年`}${day} ${time}`,
+    full: `${date.getFullYear()}年${day} ${time}:${pad(date.getSeconds())}`,
+  };
+}
+

src/pages/Chat/CodingConversationTimeline.tsx

@@ -1,5 +1,6 @@
 import { OPEN_WORK_PROMPT } from '../../../shared/coding-work-preview';
 import { CONTINUE_CODING_PROMPT, type CodingRecoveryAction } from '../../../shared/coding-recovery';
+import { MessageTimestamp } from './MessageTimestamp';
 import { CodingRecoveryCard } from './CodingRecoveryCard';
 import {
   memo,
@@ -539,6 +540,7 @@ const MessageNode = memo(function MessageNode({
             </Button>
           )}
         </div>
+        <MessageTimestamp value={node.timestamp} pending={!user && node.status === 'streaming'} label={user ? '发送时间' : '回复完成时间'} className={cn('mt-1', user && 'text-right')} />
         {!user && answerText && (
           <Button
             type="button"
@@ -1330,6 +1332,7 @@ const AssistantCommentary = memo(function AssistantCommentary({
           {blocks.length === 0 && node.status === 'aborted' && <p className="text-muted-foreground">本次处理已中止。</p>}
         </div>
       </CompactProcessText>
+      <MessageTimestamp value={node.timestamp} pending={streaming} className="mt-1" />
     </div>
   );
 });

src/pages/Chat/MessageTimestamp.tsx

@@ -0,0 +1,15 @@
+import { formatMessageTimestamp } from '@/lib/message-timestamp';
+import { cn } from '@/lib/utils';
+
+export function MessageTimestamp({ value, pending = false, label = '回复完成时间', className }: {
+  value?: number | string;
+  pending?: boolean;
+  label?: string;
+  className?: string;
+}) {
+  const formatted = pending ? undefined : formatMessageTimestamp(value);
+  const style = cn('block text-[11px] leading-5 text-muted-foreground tabular-nums', className);
+  return formatted
+    ? <time className={style} dateTime={formatted.iso} title={formatted.full} aria-label={`${label}：${formatted.full}`}>{formatted.short}</time>
+    : <span className={style} data-message-time={pending ? 'pending' : 'unknown'}>{pending ? '回复中…' : '时间未记录'}</span>;
+}

src/pages/Chat/TeacherChatPanel.tsx

@@ -13,6 +13,7 @@ import type {
 } from '../../../shared/coding-teacher';
 import { TeacherAvatar } from './TeacherAvatar';
 import { TeacherReply } from './TeacherReply';
+import { MessageTimestamp } from './MessageTimestamp';
 
 // Preserve loaded pages and the reading anchor while moving between contacts.
 // Durable messages remain Main-owned; this is only the current window's view.
@@ -514,8 +515,8 @@ export function TeacherChatPanel({
         {topic?.requests.map((request, index) => <div key={request.id} className="mb-7 space-y-4">
           {continuous && request.projectId && (index === 0 || request.projectId !== topic.requests[index - 1].projectId) && <p className="text-center text-[10px] text-muted-foreground">{request.projectName || '之前的项目'}</p>}
           {request.intent === 'check-in'
-            ? <p className="text-[11px] text-muted-foreground">智能体来看看你的进展</p>
-            : <div className="flex justify-end"><p className="consultation-user max-w-[92%] whitespace-pre-wrap break-words rounded-2xl rounded-br-sm px-4 py-3 text-[13px] leading-7">{request.text}</p></div>}
+            ? <div className="space-y-1"><p className="text-[11px] text-muted-foreground">智能体来看看你的进展</p><MessageTimestamp value={request.createdAt} label="主动检查时间" /></div>
+            : <div className="flex flex-col items-end gap-1"><p className="consultation-user max-w-[92%] whitespace-pre-wrap break-words rounded-2xl rounded-br-sm px-4 py-3 text-[13px] leading-7">{request.text}</p><MessageTimestamp value={request.createdAt} label="发送时间" className="text-right" /></div>}
           {request.references.length > 0 && <details className="text-xs text-muted-foreground"><summary>本轮引用 {request.references.length} 项</summary>{request.references.map((ref, index) => <pre className="whitespace-pre-wrap" key={index}>{ref.text}</pre>)}</details>}
           <div className="flex items-center gap-2 text-[11px] text-muted-foreground"><TeacherAvatar definition={definition} className="h-6 w-6 rounded-lg" />{definition?.name ?? label}</div>
           {!!request.toolActivity?.length && <details className="text-xs text-muted-foreground">
@@ -528,6 +529,7 @@ export function TeacherChatPanel({
               </li>)}
             </ul>
           </details>}
+          <div className="space-y-1.5">
           {request.status === 'completed' && request.replyIncomplete ? <div className="space-y-3">
             <p role="status" className="text-[13px] leading-7 text-muted-foreground">这次回复未能完整显示</p>
             {request.intent !== 'check-in' && request.text.trim() && <button type="button" disabled={helpUnavailable || !retryScopeMatches(request)} onClick={() => void send({ text: request.text, intent: request.intent }, request)} className="consultation-retry">重新回答</button>}
@@ -537,13 +539,12 @@ export function TeacherChatPanel({
               ? <p role="status" className="flex items-center gap-2 text-[13px] leading-7 text-muted-foreground"><Loader2 className="h-3.5 w-3.5 animate-spin motion-reduce:animate-none" />我看看你最近做到了哪里…</p>
               : request.status === 'completed' && <>
                 <TeacherReply text={request.response} />
-                <div className="consultation-follow-ups" aria-label="可以和智能体聊的问题">
-                  {request.suggestedQuestions?.map((question, index) => <button key={`${request.id}:${index}`} type="button" disabled={helpUnavailable} onClick={() => void send({ text: question })} className="consultation-follow-up"><span className="min-w-0 flex-1">{question}</span><ChevronRight className="h-4 w-4 shrink-0 opacity-70" aria-hidden="true" /></button>)}
-                </div>
               </>}
             {['failed', 'cancelled', 'interrupted'].includes(request.status) && <button type="button" disabled={helpUnavailable} onClick={askForSuggestions} className="consultation-retry">帮我整体看🧠</button>}
           </> : request.response ? <TeacherReply text={request.response} /> : <div className="text-[13px] leading-7">{['running', 'preparing'].includes(request.status) ? <span role="status" className="inline-flex items-center gap-2 text-muted-foreground"><Loader2 className="h-3.5 w-3.5 animate-spin motion-reduce:animate-none" />{label}正在想…</span> : ['cancelled', 'interrupted'].includes(request.status) ? '这次先停在这里。想继续时可以再说说。' : ''}</div>}
-          {request.intent !== 'suggestions' && request.status === 'completed' && !request.replyIncomplete && Boolean(request.suggestedQuestions?.length) && <div className="consultation-follow-ups" aria-label="接着聊">
+          <MessageTimestamp value={request.finishedAt} pending={['running', 'preparing'].includes(request.status)} />
+          </div>
+          {request.status === 'completed' && !request.replyIncomplete && Boolean(request.suggestedQuestions?.length) && <div className="consultation-follow-ups" aria-label={request.intent === 'suggestions' ? '可以和智能体聊的问题' : '接着聊'}>
             {request.suggestedQuestions?.map((question, index) => <button type="button" key={`${request.id}:${index}`} disabled={helpUnavailable} onClick={() => void send({ text: question })} className="consultation-follow-up"><span className="min-w-0 flex-1">{question}</span><ChevronRight className="h-4 w-4 shrink-0 opacity-70" aria-hidden="true" /></button>)}
           </div>}
           {request.status === 'completed' && !request.replyIncomplete && request.replyParseError && <p role="status" className="text-xs text-muted-foreground">回答正文已保留，部分附加内容未能显示。</p>}

src/stores/coding-conversations.ts

@@ -227,6 +227,7 @@ function optimisticNode(
     id: nodeId,
     clientRequestId,
     role: 'user',
+    timestamp: Date.now(),
     status: 'optimistic',
     blocks: [
       ...(draft.text ? [{