fix: repair webui refresh trace layout (#938)

Co-authored-by: Codex Agent <codex@hwlab.local>

internal/cloud/access-control.test.ts

@@ -1619,6 +1619,51 @@ test("access controller preserves user message when owner evidence updates with
   assert.equal(conversation.firstUserMessagePreview, userText);
 });
 
+test("access controller dedupes duplicate refreshed assistant messages by id and trace", async () => {
+  const projectId = "prj_hwpod_workbench";
+  const ownerUserId = "usr_issue932_dedupe";
+  const conversationId = "cnv_issue932_dedupe";
+  const sessionId = "ses_issue932_dedupe";
+  const traceId = "trc_issue932_dedupe";
+  const threadId = "thread-issue-932-dedupe";
+  const nowValue = "2026-06-05T09:30:00.000Z";
+  const accessController = createAccessController({ now: () => nowValue });
+
+  await accessController.recordAgentSessionOwner({
+    ownerUserId,
+    sessionId,
+    projectId,
+    agentId: "hwlab-code-agent",
+    status: "idle",
+    conversationId,
+    threadId,
+    traceId,
+    session: {
+      source: "cloud-web-react-account-sync",
+      sessionStatus: "completed",
+      lastTraceId: traceId,
+      messages: [
+        { id: "msg_issue932_user", role: "user", title: "用户", text: "你好", status: "sent", traceId, conversationId, sessionId, threadId, createdAt: nowValue },
+        { id: "msg_issue932_agent", role: "agent", title: "Code Agent 回复", text: "最终回复", status: "completed", traceId, conversationId, sessionId, threadId, createdAt: nowValue },
+        { id: "msg_issue932_agent", role: "agent", title: "Code Agent 回复", text: "最终回复", status: "completed", traceId, conversationId, sessionId, threadId, createdAt: nowValue }
+      ],
+      messageCount: 3,
+      firstUserMessagePreview: "你好",
+      valuesRedacted: true,
+      secretMaterialStored: false
+    }
+  });
+
+  const session = await accessController.getAgentSession(sessionId);
+  const conversation = await accessController.visibleConversationForActor({ id: ownerUserId, role: "user" }, conversationId, projectId, { includeArchived: true });
+
+  assert.deepEqual(session.session.messages.map((message) => message.role), ["user", "agent"]);
+  assert.deepEqual(conversation.messages.map((message) => message.role), ["user", "agent"]);
+  assert.equal(session.session.messageCount, 2);
+  assert.equal(conversation.messageCount, 2);
+  assert.equal(conversation.messages[1].text, "最终回复");
+});
+
 test("access controller restores AgentRun mapping by Code Agent traceId", async () => {
   const accessController = createAccessController({ now: () => "2026-06-01T00:00:00.000Z" });
   await accessController.recordAgentSessionOwner({

internal/cloud/access-control.ts

@@ -1872,7 +1872,9 @@ function mergeAgentSessionOwnerEvidence(nextValue, existingValue) {
   if (!next.agentRun && existing.agentRun) merged.agentRun = existing.agentRun;
   const nextCount = numberOrNull(next.messageCount);
   const existingCount = numberOrNull(existing.messageCount);
-  if (nextCount !== null || existingCount !== null) {
+  if (Array.isArray(merged.messages)) {
+    merged.messageCount = merged.messages.length;
+  } else if (nextCount !== null || existingCount !== null) {
     merged.messageCount = Math.max(nextCount ?? 0, existingCount ?? 0);
   }
   if (!next.firstUserMessagePreview && existing.firstUserMessagePreview) {
@@ -1883,16 +1885,16 @@ function mergeAgentSessionOwnerEvidence(nextValue, existingValue) {
   return merged;
 }
 function mergeAgentSessionOwnerMessages(nextMessages = [], existingMessages = [], context = {}) {
-  const next = Array.isArray(nextMessages) ? nextMessages.map(redactConversationMessage).filter(Boolean) : [];
-  if (next.some((message) => message.role === "user")) return next;
-  const existing = Array.isArray(existingMessages) ? existingMessages.map(redactConversationMessage).filter(Boolean) : [];
+  const next = dedupeConversationMessages(nextMessages);
+  if (next.some((message) => message.role === "user")) return ensureTerminalUserMessage(next, context).slice(-50);
+  const existing = dedupeConversationMessages(existingMessages);
   const merged = [...existing];
   for (const message of next) {
     const index = merged.findIndex((item) => sameConversationMessage(item, message));
-    if (index >= 0) merged[index] = message;
+    if (index >= 0) merged[index] = mergeConversationMessage(merged[index], message);
     else merged.push(message);
   }
-  return ensureTerminalUserMessage(merged, context).slice(-50);
+  return dedupeConversationMessages(ensureTerminalUserMessage(merged, context)).slice(-50);
 }
 function sameConversationMessage(left = {}, right = {}) {
   const leftId = textOr(left.id, "");
@@ -1902,6 +1904,29 @@ function sameConversationMessage(left = {}, right = {}) {
   const rightTrace = safeTraceIdLocal(right.traceId);
   return Boolean(leftTrace && rightTrace && leftTrace === rightTrace && textOr(left.role, "") === textOr(right.role, ""));
 }
+function dedupeConversationMessages(messagesSource = []) {
+  const source = Array.isArray(messagesSource) ? messagesSource : [];
+  const merged = [];
+  for (const rawMessage of source) {
+    const message = redactConversationMessage(rawMessage);
+    if (!message) continue;
+    const index = merged.findIndex((item) => sameConversationMessage(item, message));
+    if (index >= 0) merged[index] = mergeConversationMessage(merged[index], message);
+    else merged.push(message);
+  }
+  return merged.slice(-50);
+}
+function mergeConversationMessage(existing = {}, next = {}) {
+  return pruneEmpty({
+    ...existing,
+    ...next,
+    title: textOr(next.title, existing.title),
+    text: textOr(next.text, existing.text),
+    runnerTrace: next.runnerTrace ?? existing.runnerTrace,
+    updatedAt: textOr(next.updatedAt, existing.updatedAt),
+    createdAt: textOr(next.createdAt, existing.createdAt)
+  });
+}
 function firstMessageTraceId(messagesSource) {
   return safeTraceIdLocal(firstMessageField(messagesSource, "traceId")) || null;
 }
@@ -1926,7 +1951,7 @@ function normalizeWorkspacePatch(body = {}, actor = null) {
     selectedAgentSessionId: safeAgentSessionId(body.selectedAgentSessionId ?? body.sessionId ?? workspace.selectedAgentSessionId) || workspace.selectedAgentSessionId,
     activeTraceId: safeTraceIdLocal(body.activeTraceId ?? body.traceId ?? workspace.activeTraceId) || null,
     providerProfile: textOr(body.providerProfile ?? workspace.providerProfile, workspace.providerProfile ?? null),
-    messages: Array.isArray(body.messages) ? body.messages.slice(-50).map(redactConversationMessage).filter(Boolean) : Array.isArray(workspace.messages) ? workspace.messages : undefined,
+    messages: Array.isArray(body.messages) ? dedupeConversationMessages(body.messages) : Array.isArray(workspace.messages) ? dedupeConversationMessages(workspace.messages) : undefined,
     actor: actor ? publicActor(actor) : undefined,
     secretMaterialStored: false,
     valuesRedacted: true
@@ -2001,7 +2026,7 @@ function redactedWorkspaceJson(value = {}) {
     staleAgentSessionId: textOr(workspace.staleAgentSessionId, ""),
     staleThreadId: textOr(workspace.staleThreadId, ""),
     recoveryAction: textOr(workspace.recoveryAction, ""),
-    messages: Array.isArray(workspace.messages) ? workspace.messages.slice(-50).map(redactConversationMessage).filter(Boolean) : undefined,
+    messages: Array.isArray(workspace.messages) ? dedupeConversationMessages(workspace.messages) : undefined,
     actor: workspace.actor && typeof workspace.actor === "object" ? publicActor(workspace.actor) : undefined,
     updatedAt: textOr(workspace.updatedAt, ""),
     resetAt: textOr(workspace.resetAt, ""),
@@ -2016,12 +2041,14 @@ function normalizeConversationSnapshot(body = {}, actor = null) {
   const snapshot = normalizeObject(body.snapshot ?? body);
   const messagesSource = Array.isArray(body.messages) ? body.messages : snapshot.messages;
   const chatMessagesSource = Array.isArray(body.chatMessages) ? body.chatMessages : snapshot.chatMessages;
+  const messages = dedupeConversationMessages(messagesSource);
+  const chatMessages = Array.isArray(chatMessagesSource) ? dedupeConversationMessages(chatMessagesSource) : undefined;
   return {
     ...snapshot,
-    messages: Array.isArray(messagesSource) ? messagesSource.slice(-50).map(redactConversationMessage).filter(Boolean) : [],
-    chatMessages: Array.isArray(chatMessagesSource) ? chatMessagesSource.slice(-50).map(redactConversationMessage).filter(Boolean) : undefined,
-    messageCount: resolveSnapshotMessageCount(messagesSource, snapshot.messageCount),
-    firstUserMessagePreview: firstUserPreviewFromMessages(messagesSource) ?? snapshot.firstUserMessagePreview ?? null,
+    messages,
+    chatMessages,
+    messageCount: resolveSnapshotMessageCount(messages, snapshot.messageCount),
+    firstUserMessagePreview: firstUserPreviewFromMessages(messages) ?? snapshot.firstUserMessagePreview ?? null,
     actor: actor ? publicActor(actor) : undefined,
     secretMaterialStored: false,
     valuesRedacted: true
@@ -2030,7 +2057,7 @@ function normalizeConversationSnapshot(body = {}, actor = null) {
 function resolveSnapshotMessageCount(messagesSource, existingCount) {
   const explicit = numberOrNull(existingCount);
   const fromSource = Array.isArray(messagesSource) ? messagesSource.length : null;
-  if (explicit !== null && fromSource !== null) return Math.max(explicit, fromSource);
+  if (fromSource !== null) return fromSource;
   return explicit ?? fromSource ?? 0;
 }
 function firstUserPreviewFromMessages(messagesSource) {
@@ -2134,14 +2161,13 @@ function isLegacyFinalResponseFallbackText(value) {
   return textOr(value, "").trim() === "Code Agent 仍在处理，可以继续 steer 或等待 trace 完成。";
 }
 function mergeTerminalConversationMessages(existingMessages = [], result = {}, context = {}) {
-  const baseMessages = Array.isArray(existingMessages) ? existingMessages.map(redactConversationMessage).filter(Boolean) : [];
+  const baseMessages = dedupeConversationMessages(existingMessages);
   const traceId = safeTraceIdLocal(result.traceId ?? context.traceId);
   const terminalStatus = terminalWorkbenchSessionStatus(result);
   const assistantText = textOr(result.reply?.content ?? result.assistantText ?? result.message?.content ?? result.error?.message ?? result.userMessage, "");
   const now = textOr(context.now, new Date().toISOString());
   const firstUserPreview = firstUserPreviewFromMessages(baseMessages) ?? textOr(context.firstUserMessagePreview, null);
-  const messages = ensureTerminalUserMessage(baseMessages, { ...context, traceId, now, firstUserPreview });
-  const existingCount = numberOrNull(context.existingMessageCount) ?? messages.length;
+  const messages = dedupeConversationMessages(ensureTerminalUserMessage(baseMessages, { ...context, traceId, now, firstUserPreview }));
   const runnerTrace = terminalRunnerTraceForConversationMessage(result, { ...context, traceId, terminalStatus });
   const next = messages.map((message) => {
     if (traceId && message.traceId === traceId && message.role === "agent") {
@@ -2176,10 +2202,10 @@ function mergeTerminalConversationMessages(existingMessages = [], result = {}, c
     }));
     addedAgentMessage = true;
   }
-  const finalMessages = next.slice(-50);
+  const finalMessages = dedupeConversationMessages(next).slice(-50);
   return {
     messages: finalMessages,
-    messageCount: Math.max(existingCount + (addedAgentMessage ? 1 : 0), finalMessages.length),
+    messageCount: finalMessages.length,
     firstUserMessagePreview: firstUserPreviewFromMessages(finalMessages) ?? firstUserPreview
   };
 }
@@ -2216,7 +2242,11 @@ function terminalRunnerTraceForConversationMessage(result = {}, context = {}) {
     eventCount: numberOrNull(source.eventCount ?? result.traceSummary?.sourceEventCount ?? result.traceSummary?.eventCount) ?? events.length,
     eventsCompacted: source.eventsCompacted === true || events.length === 0,
     fullTraceLoaded: false,
-    lastEvent
+    lastEvent,
+    traceStatus: textOr(result.traceStatus, ""),
+    fallback: redactTraceFallback(result.fallback),
+    finalResponse: redactTraceFinalResponse(result.finalResponse),
+    traceSummary: redactTraceSummary(result.traceSummary)
   });
 }
 function redactConversationMessage(message) {
@@ -2243,10 +2273,64 @@ function redactConversationMessage(message) {
       eventCount: runnerTrace.eventCount,
       eventsCompacted: runnerTrace.eventsCompacted === true,
       fullTraceLoaded: runnerTrace.fullTraceLoaded === true,
-      lastEvent: runnerTrace.lastEvent
+      lastEvent: runnerTrace.lastEvent,
+      traceStatus: textOr(runnerTrace.traceStatus, ""),
+      fallback: redactTraceFallback(runnerTrace.fallback),
+      finalResponse: redactTraceFinalResponse(runnerTrace.finalResponse),
+      traceSummary: redactTraceSummary(runnerTrace.traceSummary)
     }) : undefined
   });
 }
+function redactTraceFallback(value) {
+  const fallback = normalizeObject(value);
+  if (Object.keys(fallback).length === 0) return undefined;
+  return pruneEmpty({
+    available: fallback.available === true,
+    source: textOr(fallback.source, ""),
+    conversationId: textOr(fallback.conversationId, ""),
+    sessionId: textOr(fallback.sessionId, ""),
+    threadId: textOr(fallback.threadId, ""),
+    agentRun: redactAgentRunSummary(fallback.agentRun),
+    finalResponse: redactTraceFinalResponse(fallback.finalResponse),
+    traceSummary: redactTraceSummary(fallback.traceSummary)
+  });
+}
+function redactTraceFinalResponse(value) {
+  const response = normalizeObject(value);
+  if (Object.keys(response).length === 0) return undefined;
+  return pruneEmpty({
+    role: textOr(response.role, ""),
+    status: textOr(response.status, ""),
+    messageId: textOr(response.messageId, ""),
+    text: boundedText(response.text ?? response.content ?? response.message, 12000),
+    textPreview: boundedText(response.textPreview, 1200),
+    textChars: numberOrNull(response.textChars)
+  });
+}
+function redactTraceSummary(value) {
+  const summary = normalizeObject(value);
+  if (Object.keys(summary).length === 0) return undefined;
+  return pruneEmpty({
+    source: textOr(summary.source, ""),
+    terminalStatus: textOr(summary.terminalStatus, ""),
+    sourceEventCount: numberOrNull(summary.sourceEventCount ?? summary.eventCount),
+    lastEventLabel: textOr(summary.lastEventLabel, ""),
+    finalAssistantRow: redactTraceFinalResponse(summary.finalAssistantRow)
+  });
+}
+function redactAgentRunSummary(value) {
+  const agentRun = normalizeObject(value);
+  if (Object.keys(agentRun).length === 0) return undefined;
+  return pruneEmpty({
+    adapter: textOr(agentRun.adapter, ""),
+    backendProfile: textOr(agentRun.backendProfile, ""),
+    runId: textOr(agentRun.runId, ""),
+    commandId: textOr(agentRun.commandId, ""),
+    jobName: textOr(agentRun.jobName, ""),
+    namespace: textOr(agentRun.namespace, ""),
+    terminalStatus: textOr(agentRun.terminalStatus, "")
+  });
+}
 function conversationsFromAgentSessions(sessions = []) {
   const byConversation = new Map();
   for (const session of sessions) {
@@ -2261,14 +2345,14 @@ function conversationsFromAgentSessions(sessions = []) {
 function publicAgentConversation(session) {
   const snapshot = normalizeObject(session.session);
   const rawMessages = Array.isArray(snapshot.messages) ? snapshot.messages : Array.isArray(snapshot.chatMessages) ? snapshot.chatMessages : [];
-  const messages = ensureTerminalUserMessage(rawMessages, {
+  const messages = dedupeConversationMessages(ensureTerminalUserMessage(rawMessages, {
     traceId: session.lastTraceId ?? snapshot.lastTraceId,
     conversationId: session.conversationId,
     sessionId: session.id,
     threadId: session.threadId,
     now: session.updatedAt,
     firstUserPreview: snapshot.firstUserMessagePreview
-  });
+  }));
   const status = resolvedConversationStatus(session.status, snapshot, messages);
   const lastTraceId = resolvedConversationLastTraceId(session.lastTraceId, status, messages, snapshot);
   return {
@@ -2285,7 +2369,7 @@ function publicAgentConversation(session) {
     endedAt: session.endedAt,
     session: pruneEmpty({ sessionId: session.id, threadId: session.threadId, status }),
     messages,
-    messageCount: numberOrNull(snapshot.messageCount) ?? messages.length,
+    messageCount: messages.length,
     firstUserMessagePreview: textOr(snapshot.firstUserMessagePreview, null),
     snapshot: pruneEmpty({
       sessionStatus: snapshot.sessionStatus,

web/hwlab-cloud-web/src/components/conversation/MessageTracePanel.test.tsx

@@ -55,3 +55,23 @@ test("message trace panel exposes running status for live trace animation", () =
   assert.match(html, /data-trace-status="running"/u);
   assert.match(html, /open=""/u);
 });
+
+test("message trace panel renders persisted fallback for expired historical trace", () => {
+  const trace: RunnerTrace = {
+    traceId: "trc_issue932_expired",
+    status: "expired",
+    traceStatus: "expired",
+    events: [],
+    eventCount: 31,
+    fallback: { available: true, source: "agent-session-snapshot" },
+    traceSummary: { sourceEventCount: 31, terminalStatus: "completed", source: "agent-session-snapshot" },
+    finalResponse: { text: "历史最终回复" }
+  };
+
+  const html = renderToStaticMarkup(<MessageTracePanel trace={trace} defaultOpen />);
+
+  assert.match(html, /历史 trace 已过期/u);
+  assert.match(html, /历史最终回复/u);
+  assert.match(html, /sourceEventCount=31/u);
+  assert.doesNotMatch(html, /等待后端事件/u);
+});

web/hwlab-cloud-web/src/components/conversation/MessageTracePanel.tsx

@@ -46,7 +46,10 @@ export function MessageTracePanel({ trace, defaultOpen, storageKey, markdownUpgr
 
   const events = Array.isArray(trace.events) ? trace.events : [];
   const last = summarizeLastEvent(trace);
-  const rows = useMemo<TraceEventRow[]>(() => traceDisplayRows(trace, events), [trace, events]);
+  const rows = useMemo<TraceEventRow[]>(() => {
+    const eventRows = traceDisplayRows(trace, events);
+    return eventRows.length > 0 ? eventRows : persistentTraceFallbackRows(trace);
+  }, [trace, events]);
   const noiseCount = useMemo<number>(() => traceNoiseEventCount(events), [events]);
   const lastUpdatedAt = traceUpdatedAt(trace, events, last.ts);
 
@@ -113,6 +116,42 @@ function traceCountText(trace: RunnerTrace, events: number, rows: number, noiseC
   return `${rows}/${events}/${rawTotal} 行${noise}`;
 }
 
+function persistentTraceFallbackRows(trace: RunnerTrace): TraceEventRow[] {
+  const fallback = objectOrNull(trace.fallback);
+  const summary = objectOrNull(trace.traceSummary);
+  const response = objectOrNull(trace.finalResponse);
+  const text = firstNonEmptyTraceText(response?.text, response?.content, response?.message, summary?.finalText, summary?.text);
+  const sourceCount = positiveInteger(summary?.sourceEventCount ?? summary?.eventCount ?? trace.eventCount);
+  if (!text && fallback?.available !== true && sourceCount === 0) return [];
+  const status = firstNonEmptyTraceText(trace.traceStatus, trace.status, summary?.terminalStatus, objectOrNull(trace.agentRun)?.terminalStatus) ?? "expired";
+  const header = `${trace.traceId ?? "trace"} 历史 trace 已过期，显示持久化摘要`;
+  const meta = [
+    `traceStatus=${status}`,
+    sourceCount > 0 ? `sourceEventCount=${sourceCount}` : null,
+    firstNonEmptyTraceText(fallback?.source, summary?.source) ? `source=${firstNonEmptyTraceText(fallback?.source, summary?.source)}` : null
+  ].filter(Boolean).join("\n");
+  const body = [meta, text].filter(Boolean).join("\n\n") || "后端没有保留原始 event，但已返回持久化 trace 摘要。";
+  return [{ rowId: `fallback:${trace.traceId ?? "trace"}`, seq: null, tone: "source", header, body, terminal: true, bodyFormat: text ? "markdown" : "text" }];
+}
+
+function objectOrNull(value: unknown): Record<string, unknown> | null {
+  return value && typeof value === "object" ? value as Record<string, unknown> : null;
+}
+
+function firstNonEmptyTraceText(...values: unknown[]): string | null {
+  for (const value of values) {
+    if (typeof value !== "string") continue;
+    const text = value.trim();
+    if (text) return text;
+  }
+  return null;
+}
+
+function positiveInteger(value: unknown): number {
+  const parsed = Number(value);
+  return Number.isInteger(parsed) && parsed > 0 ? parsed : 0;
+}
+
 function isRunningTrace(trace: RunnerTrace): boolean {
   return String(trace.status ?? "").toLowerCase() === "running";
 }

web/hwlab-cloud-web/src/state/conversation.test.ts

@@ -0,0 +1,52 @@
+import assert from "node:assert/strict";
+import { test } from "bun:test";
+
+import { mergeConversationMessages } from "./conversation";
+import type { ChatMessage } from "../types/domain";
+
+test("mergeConversationMessages replaces a refreshed agent message instead of appending a duplicate", () => {
+  const base: ChatMessage[] = [
+    message({ id: "msg_user", role: "user", text: "你好", status: "sent" }),
+    message({ id: "msg_agent", role: "agent", text: "处理中", status: "running" })
+  ];
+
+  const merged = mergeConversationMessages(base, [
+    message({ id: "msg_agent", role: "agent", text: "完成回复", status: "completed", updatedAt: "2026-06-05T10:00:00.000Z" })
+  ]);
+
+  assert.equal(merged.length, 2);
+  const agent = merged[1];
+  assert.ok(agent);
+  assert.equal(agent.text, "完成回复");
+  assert.equal(agent.status, "completed");
+});
+
+test("mergeConversationMessages dedupes same trace and role when a refresh generated a new local id", () => {
+  const merged = mergeConversationMessages([
+    message({ id: "msg_agent_old", role: "agent", text: "旧回复", status: "running" })
+  ], [
+    message({ id: "msg_agent_new", role: "agent", text: "最终回复", status: "completed" })
+  ]);
+
+  assert.equal(merged.length, 1);
+  const agent = merged[0];
+  assert.ok(agent);
+  assert.equal(agent.id, "msg_agent_new");
+  assert.equal(agent.text, "最终回复");
+});
+
+function message(overrides: Partial<ChatMessage>): ChatMessage {
+  return {
+    id: "msg_default",
+    role: "agent",
+    title: "Code Agent",
+    text: "",
+    status: "running",
+    traceId: "trc_issue932_refresh",
+    conversationId: "cnv_issue932_refresh",
+    sessionId: "ses_issue932_refresh",
+    threadId: "thread-issue932-refresh",
+    createdAt: "2026-06-05T09:59:00.000Z",
+    ...overrides
+  };
+}

web/hwlab-cloud-web/src/state/conversation.ts

@@ -14,6 +14,36 @@ export function makeMessage(role: "user" | "agent", text: string, status: ChatMe
   return { id: nextProtocolId("msg"), role, title: meta.title ?? (role === "user" ? "用户" : "Code Agent"), text, status, traceId: meta.traceId, conversationId: meta.conversationId, sessionId: meta.sessionId, threadId: meta.threadId, createdAt: new Date().toISOString() };
 }
 
+export function mergeConversationMessages(existing: ChatMessage[], incoming: ChatMessage[] = []): ChatMessage[] {
+  const merged: ChatMessage[] = [];
+  for (const message of [...existing, ...incoming]) {
+    const index = merged.findIndex((item) => sameConversationMessage(item, message));
+    const current = index >= 0 ? merged[index] : null;
+    if (current) merged[index] = mergeConversationMessage(current, message);
+    else merged.push(message);
+  }
+  return merged;
+}
+
+function mergeConversationMessage(existing: ChatMessage, next: ChatMessage): ChatMessage {
+  return {
+    ...existing,
+    ...next,
+    title: firstNonEmptyString(next.title, existing.title) ?? next.title,
+    text: firstNonEmptyString(next.text, existing.text) ?? next.text,
+    runnerTrace: next.runnerTrace ?? existing.runnerTrace,
+    traceEvents: next.traceEvents ?? existing.traceEvents,
+    error: next.error ?? existing.error,
+    updatedAt: next.updatedAt ?? existing.updatedAt
+  };
+}
+
+function sameConversationMessage(left: ChatMessage, right: ChatMessage): boolean {
+  if (left.id && right.id && left.id === right.id) return true;
+  if (!left.traceId || !right.traceId || left.traceId !== right.traceId || left.role !== right.role) return false;
+  return !left.conversationId || !right.conversationId || left.conversationId === right.conversationId;
+}
+
 export function messageFromAgentResponse(messageId: string, pending: ChatMessage, response: AgentChatResponse | AgentChatResultResponse): ChatMessage {
   const errorObject = typeof response.error === "object" && response.error ? response.error : null;
   const failed = Boolean(response.error) || ["failed", "blocked", "timeout", "cancelled"].includes(String(response.status ?? ""));
@@ -96,15 +126,17 @@ export async function ensureWorkspace(current: WorkspaceRecord | null): Promise<
 }
 
 export async function persistConversation(input: { workspace: WorkspaceRecord | null; conversationId: string; sessionId: string | null; threadId: string | null; messages: ChatMessage[] }): Promise<WorkspaceRecord | null> {
+  const messages = mergeConversationMessages(input.messages);
+  const latest = messages.at(-1);
   await api.saveConversation(input.conversationId, {
     projectId: WORKBENCH_PROJECT_ID,
     conversationId: input.conversationId,
     sessionId: input.sessionId,
     threadId: input.threadId,
-    sessionStatus: input.messages.at(-1)?.status ?? "source",
-    lastTraceId: input.messages.at(-1)?.traceId,
-    messages: input.messages,
-    snapshot: { source: "cloud-web-react-account-sync", updatedAt: new Date().toISOString(), sessionStatus: input.messages.at(-1)?.status ?? "source" }
+    sessionStatus: latest?.status ?? "source",
+    lastTraceId: latest?.traceId,
+    messages,
+    snapshot: { source: "cloud-web-react-account-sync", updatedAt: new Date().toISOString(), sessionStatus: latest?.status ?? "source" }
   });
   if (input.workspace?.workspaceId) {
     const response = await api.updateWorkspace(input.workspace.workspaceId, {
@@ -113,8 +145,8 @@ export async function persistConversation(input: { workspace: WorkspaceRecord |
       selectedConversationId: input.conversationId,
       selectedAgentSessionId: input.sessionId,
       threadId: input.threadId,
-      activeTraceId: input.messages.findLast((message) => message.status === "running")?.traceId ?? null,
-      messages: input.messages,
+      activeTraceId: messages.findLast((message) => message.status === "running")?.traceId ?? null,
+      messages,
       workspace: { source: "cloud-web-react-workspace-sync", updatedAt: new Date().toISOString() },
       updatedByClient: "cloud-web-react"
     });

web/hwlab-cloud-web/src/state/issue853-refresh-regression.test.ts

@@ -29,8 +29,9 @@ test("issue 853 submit failure persists the same trace before refresh", () => {
 
 test("issue 853 left sidebar collapse only removes the left columns", () => {
   const css = fs.readFileSync(path.join(srcRoot, "styles/workbench.css"), "utf8");
-  assert.match(css, /\.workbench-shell\.is-left-sidebar-collapsed \.workspace-body \{ grid-template-columns: 0 0 minmax\(0, 1fr\) var\(--resize-handle-width\) var\(--right-sidebar-width\); \}/u);
-  assert.doesNotMatch(css, /\.workbench-shell\.is-left-sidebar-collapsed \.workspace-body \{ grid-template-columns: 0 0 minmax\(420px, 1fr\)/u);
+  assert.match(css, /--right-sidebar-left-collapsed-width: min\(var\(--right-sidebar-width\), 46vw\);/u);
+  assert.match(css, /\.workbench-shell\.is-left-sidebar-collapsed \.workspace-body \{ grid-template-columns: 0 0 minmax\(360px, 1fr\) var\(--resize-handle-width\) minmax\(min\(var\(--right-sidebar-min-width\), 46vw\), var\(--right-sidebar-left-collapsed-width\)\); \}/u);
+  assert.doesNotMatch(css, /\.workbench-shell\.is-left-sidebar-collapsed \.workspace-body \{ grid-template-columns: 0 0 minmax\(0, 1fr\) var\(--resize-handle-width\) var\(--right-sidebar-width\); \}/u);
 });
 
 test("issue 853 completed trace panels keep stored open state instead of closing on refresh", () => {

web/hwlab-cloud-web/src/state/runner-trace.test.ts

@@ -379,6 +379,36 @@ test("fetchTraceSnapshot retries until fast-fail trace events are readable", asy
   }
 });
 
+test("fetchTraceSnapshot accepts expired trace fallback without waiting for raw events", async () => {
+  const originalFetch = globalThis.fetch;
+  const fetches: string[] = [];
+  globalThis.fetch = (async (input: RequestInfo | URL) => {
+    const url = String(input);
+    fetches.push(url);
+    return jsonResponse({
+      status: "completed",
+      traceStatus: "expired",
+      traceId: "trc_expired_fallback",
+      events: [],
+      eventCount: 0,
+      fallback: { available: true, source: "agent-session-snapshot" },
+      traceSummary: { sourceEventCount: 31, terminalStatus: "completed" },
+      finalResponse: { text: "过期 trace 的最终回复" }
+    });
+  }) as typeof fetch;
+
+  try {
+    const snapshot = await fetchTraceSnapshot("trc_expired_fallback", "trc_expired_fallback", 1000);
+    assert.equal(snapshot?.status, "expired");
+    assert.equal(snapshot?.eventCount, 31);
+    assert.equal((snapshot?.fallback as { source?: string })?.source, "agent-session-snapshot");
+    assert.equal((snapshot?.finalResponse as { text?: string })?.text, "过期 trace 的最终回复");
+    assert.equal(fetches.length, 1);
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});
+
 function jsonResponse(payload: unknown): Response {
   return new Response(JSON.stringify(payload), { status: 200, headers: { "content-type": "application/json" } });
 }

web/hwlab-cloud-web/src/state/runner-trace.ts

@@ -17,6 +17,11 @@ export interface TraceSnapshot {
   eventCount?: number;
   eventsCompacted?: boolean;
   agentRun?: AgentRunProvenance;
+  traceStatus?: string;
+  retention?: unknown;
+  fallback?: unknown;
+  finalResponse?: unknown;
+  traceSummary?: unknown;
   lastEventLabel?: string;
   waitingFor?: string;
   updatedAt?: string;
@@ -67,6 +72,12 @@ export function snapshotToRunnerTrace(snapshot: TraceSnapshot): NonNullable<Chat
     events,
     eventCount: snapshot.eventCount ?? events.length,
     eventsCompacted: snapshot.eventsCompacted,
+    traceStatus: snapshot.traceStatus,
+    retention: snapshot.retention,
+    fallback: snapshot.fallback,
+    finalResponse: snapshot.finalResponse,
+    traceSummary: snapshot.traceSummary,
+    agentRun: snapshot.agentRun,
     runnerKind: snapshot.agentRun?.adapter,
     sessionMode: snapshot.agentRun?.backendProfile,
     lastEventLabel: snapshot.lastEventLabel ?? events.at(-1)?.label ?? events.at(-1)?.type,
@@ -95,6 +106,11 @@ export function mergeTraceResults(terminal: AgentChatResultResponse, trace: Trac
     traceEvents: terminal.traceEvents ?? events,
     events,
     eventCount: trace.eventCount ?? events.length,
+    traceStatus: trace.traceStatus ?? terminal.traceStatus,
+    retention: trace.retention ?? terminal.retention,
+    fallback: trace.fallback ?? terminal.fallback,
+    finalResponse: trace.finalResponse ?? terminal.finalResponse,
+    traceSummary: trace.traceSummary ?? terminal.traceSummary,
     lastEventLabel: trace.lastEventLabel ?? terminal.lastEventLabel ?? events.at(-1)?.label
   } as AgentChatResultResponse;
 }
@@ -264,6 +280,11 @@ export async function subscribeToTrace(config: TraceSubscriptionConfig): Promise
           eventCount,
           eventsCompacted: false,
           agentRun: tracePolled.data.agentRun,
+          traceStatus: typeof tracePolled.data.traceStatus === "string" ? tracePolled.data.traceStatus : undefined,
+          retention: tracePolled.data.retention,
+          fallback: tracePolled.data.fallback,
+          finalResponse: tracePolled.data.finalResponse,
+          traceSummary: tracePolled.data.traceSummary,
           lastEventLabel: String(lastEvent?.label ?? lastEvent?.type ?? tracePolled.data.lastEventLabel ?? ""),
           waitingFor: String(tracePolled.data.waitingFor ?? ""),
           updatedAt: updatedAt ?? new Date().toISOString()
@@ -330,7 +351,7 @@ export async function fetchTraceSnapshot(traceId: string, traceUrlOrId: string,
     if (signal?.aborted) return null;
     if (tracePolled.ok && tracePolled.data) {
       const snapshot = snapshotFromTracePoll(traceId, tracePolled.data);
-      if (hasTraceEvents(snapshot)) return snapshot;
+      if (hasTraceEvents(snapshot) || hasPersistedTraceFallback(snapshot)) return snapshot;
     }
     if (attempts >= maxAttempts || Date.now() - startedAt >= totalTimeoutMs) break;
     await new Promise<void>((resolve) => window.setTimeout(resolve, Math.min(TRACE_SNAPSHOT_RETRY_INTERVAL_MS, totalTimeoutMs - (Date.now() - startedAt))));
@@ -345,7 +366,7 @@ function snapshotFromTracePoll(traceId: string, result: AgentChatResultResponse)
     ...result,
     traceId,
     events,
-    eventCount: Number(result.eventCount ?? events.length) || 0,
+    eventCount: traceSnapshotEventCount(result, events),
     lastEventLabel: String(last?.label ?? last?.type ?? result.lastEventLabel ?? "")
   } as AgentChatResultResponse);
 }
@@ -354,15 +375,31 @@ function hasTraceEvents(snapshot: TraceSnapshot): boolean {
   return Array.isArray(snapshot.events) && snapshot.events.length > 0;
 }
 
+function hasPersistedTraceFallback(snapshot: TraceSnapshot): boolean {
+  const fallback = objectOrNull(snapshot.fallback);
+  const summary = objectOrNull(snapshot.traceSummary);
+  return Boolean(
+    fallback?.available === true ||
+    finalResponseText(snapshot.finalResponse) ||
+    positiveNumber(summary?.sourceEventCount ?? summary?.eventCount) > 0
+  );
+}
+
 function snapshotToTraceSnapshot(result: AgentChatResultResponse): TraceSnapshot {
   const events = Array.isArray((result as { events?: TraceEvent[] }).events) ? ((result as { events?: TraceEvent[] }).events ?? []) : [];
+  const traceStatus = firstNonEmptyString(result.traceStatus, result.status);
   return {
     traceId: result.traceId,
-    status: result.status,
+    status: traceStatus ?? result.status,
     sessionId: result.sessionId ?? null,
     threadId: result.threadId ?? null,
     events,
-    eventCount: Number(result.eventCount ?? events.length) || 0,
+    eventCount: traceSnapshotEventCount(result, events),
+    traceStatus: typeof result.traceStatus === "string" ? result.traceStatus : undefined,
+    retention: result.retention,
+    fallback: result.fallback,
+    finalResponse: result.finalResponse,
+    traceSummary: result.traceSummary,
     agentRun: result.agentRun,
     lastEventLabel: typeof result.lastEventLabel === "string" ? result.lastEventLabel : String(events.at(-1)?.label ?? events.at(-1)?.type ?? ""),
     updatedAt: typeof result.updatedAt === "string" ? result.updatedAt : new Date().toISOString()
@@ -378,15 +415,26 @@ export async function replayFullTrace(traceId: string, totalTimeoutMs = 15000):
     polled = await api.getAgentChatResult(url, Math.max(1000, totalTimeoutMs - (Date.now() - startedAt)));
   }
   if (!polled.ok || !polled.data) return null;
-  const events = Array.isArray(polled.data.events) ? polled.data.events : [];
-  const lastEvent = events[events.length - 1];
-  return {
-    traceId,
-    status: String(polled.data.status ?? "completed"),
-    events,
-    eventCount: Number(polled.data.eventCount ?? events.length) || 0,
-    eventsCompacted: true,
-    lastEventLabel: String(lastEvent?.label ?? lastEvent?.type ?? ""),
-    updatedAt: String(polled.data.updatedAt ?? new Date().toISOString())
-  };
+  return { ...snapshotFromTracePoll(traceId, polled.data), eventsCompacted: true };
+}
+
+function traceSnapshotEventCount(result: AgentChatResultResponse, events: TraceEvent[]): number {
+  const explicit = positiveNumber(result.eventCount);
+  if (explicit > 0 || events.length > 0) return explicit || events.length;
+  const summary = objectOrNull(result.traceSummary);
+  return positiveNumber(summary?.sourceEventCount ?? summary?.eventCount) || 0;
+}
+
+function positiveNumber(value: unknown): number {
+  const parsed = Number(value);
+  return Number.isFinite(parsed) && parsed > 0 ? parsed : 0;
+}
+
+function objectOrNull(value: unknown): Record<string, unknown> | null {
+  return value && typeof value === "object" ? value as Record<string, unknown> : null;
+}
+
+function finalResponseText(value: unknown): string | null {
+  const item = objectOrNull(value);
+  return firstNonEmptyString(item?.text, item?.content, item?.message);
 }

web/hwlab-cloud-web/src/state/trace-reattach.ts

@@ -1,6 +1,6 @@
 import { useEffect } from "react";
 import { firstNonEmptyString, nextProtocolId } from "../utils";
-import { makeMessage, messageFromAgentResponse, persistConversation } from "./conversation";
+import { makeMessage, mergeConversationMessages, messageFromAgentResponse, persistConversation } from "./conversation";
 import { mergeTraceResults, snapshotToRunnerTrace, subscribeToTrace, type TraceSnapshot } from "./runner-trace";
 import type { Action } from "./workbench-reducer";
 import type { WorkbenchState } from "./workbench-state";
@@ -50,13 +50,13 @@ export function useTraceReattach(config: UseTraceReattachConfig): void {
         const stub = messages.find((m) => m.id === placeholderId) ?? ({ id: placeholderId, role: "agent" as const, text: "", status: "running" as const, traceId: activeTraceId, conversationId, sessionId, threadId, createdAt: new Date().toISOString() } as ChatMessage);
         const completed = messageFromAgentResponse(placeholderId, stub, mergeTraceResults(result, lastSnapshot));
         onDispatch({ type: "message:complete", messageId: placeholderId, message: completed, availability: result.availability ?? null, workspace: ws ?? undefined });
-        void onPersist({ workspace: ws, conversationId, sessionId: result.sessionId ?? sessionId, threadId: result.threadId ?? threadId, messages: [...messages, completed] });
+        void onPersist({ workspace: ws, conversationId, sessionId: result.sessionId ?? sessionId, threadId: result.threadId ?? threadId, messages: mergeConversationMessages(messages, [completed]) });
         controller.abort();
       },
       onInfrastructureError: (error) => {
         const failed = makeMessage("agent", `Code Agent re-attach ${codeAgentTimeoutMs}ms 无活动（${error}）`, "failed", { traceId: activeTraceId, conversationId, sessionId, threadId, title: "Code Agent 超时" });
         onDispatch({ type: "message:fail", messageId: placeholderId, message: failed });
-        void onPersist({ workspace: ws, conversationId, sessionId, threadId, messages: [...messages, failed] });
+        void onPersist({ workspace: ws, conversationId, sessionId, threadId, messages: mergeConversationMessages(messages, [failed]) });
         controller.abort();
       }
     }).finally(() => controller.abort());

web/hwlab-cloud-web/src/styles/workbench.css

@@ -19,6 +19,7 @@
   --right-sidebar-width: 620px;
   --right-sidebar-min-width: 420px;
   --right-sidebar-max-width: 680px;
+  --right-sidebar-left-collapsed-width: min(var(--right-sidebar-width), 46vw);
   --right-collapsed-width: 46px;
   --resize-handle-width: 8px;
 }
@@ -55,7 +56,7 @@ button:disabled { cursor: not-allowed; opacity: 0.55; }
 .status-chip-label { flex: 0 0 auto; }
 .status-chip-meta { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--muted); font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 11px; }
 .workspace-body { min-width: 0; min-height: 0; display: grid; grid-template-columns: var(--session-sidebar-width) var(--resize-handle-width) minmax(420px, 1fr) var(--resize-handle-width) var(--right-sidebar-width); grid-template-rows: minmax(0, 1fr); overflow: hidden; }
-.workbench-shell.is-left-sidebar-collapsed .workspace-body { grid-template-columns: 0 0 minmax(0, 1fr) var(--resize-handle-width) var(--right-sidebar-width); }
+.workbench-shell.is-left-sidebar-collapsed .workspace-body { grid-template-columns: 0 0 minmax(360px, 1fr) var(--resize-handle-width) minmax(min(var(--right-sidebar-min-width), 46vw), var(--right-sidebar-left-collapsed-width)); }
 .workbench-shell.is-right-sidebar-collapsed .workspace-body { grid-template-columns: var(--session-sidebar-width) var(--resize-handle-width) minmax(420px, 1fr) 0 0; }
 .workbench-shell.is-left-sidebar-collapsed.is-right-sidebar-collapsed .workspace-body { grid-template-columns: 0 0 minmax(0, 1fr) 0 0; }
 .workspace-body.is-route-without-sidebars { grid-template-columns: minmax(0, 1fr); }