fix(web): restrict message forks to completed turn tails

2026-08-02 16:25:02 +08:00
parent ab320ba991
commit 76547dfe0c
39 changed files with 283 additions and 73 deletions
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/client/ui-conversation/README.md
-README.md: 65e4542e622713e2cd120906926fc0601ef280bd
-README.zh.md: 4828ad214bb5ec0a9921307dd01dcc282910b330
+README.md: e351880066ac00677ab9d22c96ea75e2244a2ecf
+README.zh.md: f7c7e3ab6d341f9b3d0866951ab80a18d5968044
@@ -57,8 +57,8 @@ None; this package neither assembles nor sends a provider request.
 - **Compaction markers show no scale** — the row does not yet report how many messages or which range the checkpoint replaced.
 - **Stats-line durations cover the in-window flow only** — LLM and tool wall times fold the snapshot's assistant `timing` and tool call/result pairs, so nodes outside the loaded event window (older history) are not counted.
 - **Details panel is the minimal form and currently has no entry point** — selected call args/result raw display; the Input/Output/Metadata switch, Prev/Next stepping, and See-in-trajectory deep link are deferred. Tool rows stopped being details-panel click targets and nothing replaced that gesture, so `ChatViewInjected.openDetails` is implemented but uncalled and the panel (including its terminal card) is unreachable in the assembled application; its rendering stays covered by mounting it with a selection directly.
- **Assistant per-message paging is a reserved slot** — drawn in the design, not implemented. The finalized content IconActions row (copy / branch / clock) ships under the last content-text assistant of each turn only; mid-turn narration and Think-only nodes stay chrome-free. Branch forks through the turn containing that message, increments the inherited title on the client, and then opens the child, while a fork or rename failure leaves the source selected.
- **Sent user messages cannot be edited** — the user bubble's IconActions row carries clock / copy / branch only, and branching from the message is the nearest gesture. The control returns with the capability behind it: a client mutation over a settled user message, plus the host behavior for the turn that already consumed it ([decision](../../../.agents/notes/implemented/simplification/2026-07-31-drop-user-message-edit-stub.md)).
+- **Assistant per-message paging is a reserved slot** — drawn in the design, not implemented. The finalized content IconActions row (copy / clock, plus branch when eligible) ships under the last content-text assistant of each turn only; mid-turn narration and Think-only nodes stay chrome-free. Branch appears only when that message is also the last transcript node of a completed turn, then forks through that turn, increments the inherited title on the client, and opens the child; a fork or rename failure leaves the source selected ([decision](../../../.agents/notes/implemented/bug-fix/2026-08-02-message-fork-actions-require-completed-turn-tail.md)).
+- **Sent user messages cannot be edited** — user bubbles retain clock and copy, while branch appears only for a completed turn whose transcript ends at that user message. Editing returns with the capability behind it: a client mutation over a settled user message, plus the host behavior for the turn that already consumed it ([decision](../../../.agents/notes/implemented/simplification/2026-07-31-drop-user-message-edit-stub.md)).
 - **The sparkle icon for the others tool row is a hand-drawn approximation** — the design glyph's vector geometry is not exportable locally; promotion into ui-primitives waits on an exact export.
 - **The approval panel's "Always allow this type" is deferred** — durable grants need a grant-storage design; only allow-once/reject answer today.
 - **TodoPanel truncates long item text to one ellipsized line** — the figma strip has no wrap or expand affordance; full text is not readable inline.
@@ -57,8 +57,8 @@ todo 两个面就是在该形状上的两个注册项，都是普通注册方插
 - **压缩标记不显示规模**：该行尚不报告检查点替换了多少条消息或哪段范围。
 - **统计行的耗时只覆盖窗口内消息流**：LLM 与工具墙钟时间由快照的 assistant `timing` 与工具 call/result 配对折算，落在已加载事件窗口之外的节点（更早的历史）不计入。
 - **详情面板是最小形态，且当前没有入口**：以原始形式显示已选择调用的参数／结果；Input/Output/Metadata 切换、Prev/Next 步进与 See-in-trajectory 深链接暂缓实现。工具行已不再是详情面板的点击目标，且没有任何手势接替它，因此 `ChatViewInjected.openDetails` 虽已实现却无人调用，该面板（含其终端卡片）在组装后的应用中不可达；其渲染仍由直接以选中态挂载它来覆盖。
- **assistant 逐消息分页是预留 slot**：设计中已有图稿，尚未实现。已定稿的内容 IconActions 行（复制／分支／时钟）只挂在每个轮次中最后一条带 text 内容的 assistant 下；轮次中间的叙述与纯 Think 节点不带 chrome。分支会 fork 到包含该消息的轮次末尾，在 client 端递增继承标题后打开子会话，而 fork 或改名失败时源会话保持选中。
- **已发送的 user 消息无法编辑**：user 气泡的 IconActions 行只有时钟／复制／分支，从该消息分支是最接近的手势。该控件要与其背后的能力一起回归：既需要针对已定稿 user 消息的 client 变更，也需要 host 侧对已经消费过它的轮次给出行为（[决策](../../../.agents/notes/implemented/simplification/2026-07-31-drop-user-message-edit-stub.md)）。
+- **assistant 逐消息分页是预留 slot**：设计中已有图稿，尚未实现。已定稿的内容 IconActions 行（复制／时钟，符合条件时再显示分支）只挂在每个轮次中最后一条带 text 内容的 assistant 下；轮次中间的叙述与纯 Think 节点不带 chrome。只有当该消息同时也是已完成轮次的最后一个 transcript 节点时才显示分支；随后 fork 到该轮次末尾，在 client 端递增继承标题并打开子会话；fork 或改名失败时源会话保持选中（[决策](../../../.agents/notes/implemented/bug-fix/2026-08-02-message-fork-actions-require-completed-turn-tail.md)）。
+- **已发送的 user 消息无法编辑**：user 气泡保留时钟和复制；仅当已完成轮次的 transcript 结束于该 user 消息时才显示分支。编辑功能要与其背后的能力一起回归：既需要针对已定稿 user 消息的 client 变更，也需要 host 侧对已经消费过它的轮次给出行为（[决策](../../../.agents/notes/implemented/simplification/2026-07-31-drop-user-message-edit-stub.md)）。
 - **others 工具行的闪光图标是手绘近似版本**：无法在本地导出设计字形的矢量几何；等到存在精确导出后再将其提升到 ui-primitives。
 - **审批面板的「始终允许此类」暂缓**：持久授权需要授权存储设计；今天只能回答允许一次／拒绝。
 - **TodoPanel 将过长条目截成单行省略号**：figma 条没有换行或展开入口，完整文本无法在行内读完。
@@ -4,9 +4,10 @@
 // view groups them into tool rows through its keyed toolview slot (figma
 // step-summary flow). Shared by finalized nodes and the streaming partial;
 // the turn-level loading dots live in the chat view's tail, not here.
-// Finalized turn-tail content (text) nodes append IconActions once streaming
-// ends (`time` is omitted for mid-turn narration); Think / tool-head-only
-// nodes stay chrome-free.
+// Finalized content (text) nodes append IconActions once streaming ends
+// (`time` is omitted for mid-turn narration); their branch action is present
+// only when the node is also the completed turn's transcript tail. Think /
+// tool-head-only nodes stay chrome-free.

 import { memo, useMemo } from 'react'
 import type { AssistantBlock } from '@deepseek-ai/dsh-client-runtime/client'
@@ -28,7 +29,7 @@ export interface AssistantMarkdownProps {
  time?: number | undefined
  /** Event sequence used as the fork boundary; omitted while streaming. */
  seq?: number | undefined
-  /** Fork the session through the turn containing this finalized message. */
+  /** Fork the session through this finalized message's completed turn. */
  onFork?: ((seq: number) => void) | undefined
  /** The owning view's locale seat, passed down as a plain prop. */
  t: ChatViewSlotProps['t']
@@ -30,7 +30,7 @@ import type {
 import type { SnapshotSelectorHook } from '@deepseek-ai/dsh-client-ui-slots'
 import { IconChevronDownOutline14 } from '@deepseek-ai/dsh-client-ui-primitives'
 import type { ChatViewSlotProps } from '../contract/slots.ts'
-import { assistantActionsSeqs, deriveChatFlow, type ChatFlowItem } from './chat-flow.ts'
+import { assistantActionsSeqs, deriveChatFlow, messageBranchSeqs, type ChatFlowItem } from './chat-flow.ts'
 import { AssistantMarkdown } from './AssistantMarkdown.tsx'
 import { GenericCommandCard } from './GenericCommandCard.tsx'
 import { GenericToolCard } from './GenericToolCard.tsx'
@@ -236,6 +236,7 @@ export function ChatView({
  useSession, useSessions, useStore, renderSlot, sessionId, openFile, loadOlder, inspectCall, chatScroll, forkAt, t,
 }: ChatViewSlotProps) {
  const nodes = useSession(s => s.nodes)
+  const turnEnds = useSession(s => s.turnEnds)
  // Workspace root off the session list row: path summaries display relative to it.
  const cwd = useSessions(s => s.byId[sessionId]?.cwd)
  const running = useSession(s => s.running)
@@ -252,6 +253,7 @@ export function ChatView({
  // Only the last content assistant of each turn owns IconActions; mid-turn
  // text (before tools) omits `time` so AssistantMarkdown stays chrome-free.
  const actionSeqs = useMemo(() => assistantActionsSeqs(nodes), [nodes])
+  const branchSeqs = useMemo(() => messageBranchSeqs(nodes, turnEnds), [nodes, turnEnds])

  const listRef = useRef<HTMLDivElement | null>(null)
  const atBottomRef = useRef(true)
@@ -401,7 +403,7 @@ export function ChatView({
          interrupted={node.interrupted}
          time={actionSeqs.has(node.seq) ? node.time : undefined}
          seq={node.seq}
-          onFork={forkAt}
+          onFork={branchSeqs.has(node.seq) ? forkAt : undefined}
          t={t}
        />
      )
@@ -416,7 +418,7 @@ export function ChatView({
        key={item.key}
        node={node}
        retryActive={node.kind === 'model-retry' && node.seq === activeRetry}
-        onFork={forkAt}
+        {...branchSeqs.has(node.seq) ? { onFork: forkAt } : {}}
        t={t}
      />
    )
@@ -17,7 +17,7 @@ export interface MessageIconActionsProps {
  time: number
  /** Clock before icons (user) or after (assistant). */
  clock: 'start' | 'end'
-  /** Fork the session at this message. */
+  /** Fork the session at this message; omission hides the branch action. */
  onBranch?: (() => void) | undefined
  /** Parent layout class composed onto the actions row. */
  className?: string | undefined
@@ -50,11 +50,13 @@ export function MessageIconActions({
          <IconCopyOutline16 />
        </button>
      </Tooltip>
-      <Tooltip label={t('message.branch')} side="bottom">
-        <button type="button" className={css.action} aria-label={t('message.branch')} onClick={onBranch}>
-          <IconBranchOutline16 />
-        </button>
-      </Tooltip>
+      {onBranch !== undefined && (
+        <Tooltip label={t('message.branch')} side="bottom">
+          <button type="button" className={css.action} aria-label={t('message.branch')} onClick={onBranch}>
+            <IconBranchOutline16 />
+          </button>
+        </Tooltip>
+      )}
      {clock === 'end' ? clockEl : null}
    </div>
  )
@@ -26,7 +26,7 @@ export interface MessageItemProps {
    | TurnErrorNode
    | UnknownSurfaceNode
  retryActive?: boolean
-  /** Fork the session through the turn containing this message (user-bubble branch action). */
+  /** Fork through this message's completed turn when it is the transcript tail. */
  onFork?: (seq: number) => void
  /** The owning view's locale seat, passed down as a plain prop. */
  t: ChatViewSlotProps['t']
@@ -5,8 +5,8 @@
 * reuse the first notice's row while projecting the latest retry turn.
 * Item identity keys are stable across snapshots so the list parent can
 * subscribe to keys only while rows subscribe to content. IconActions ownership
- * (last content assistant per turn) is derived here too so ChatView and the
- * flow share one gate.
+ * and completed-turn branch points are derived here too so ChatView and the
+ * flow share their gates.
 */
 import type {
  AssistantBlock, ConversationNode, ToolResultNode,
@@ -47,6 +47,38 @@ export function assistantActionsSeqs(nodes: readonly ConversationNode[]): Readon
  return new Set(lastByTurn.values())
 }

+/**
+ * Seq set of message rows that may fork: the last transcript node of a
+ * completed turn, when that node owns message chrome. A later tool, reasoning,
+ * error, or other transcript node suppresses the earlier message's branch
+ * action even though the Host would include the whole turn.
+ * @param nodes - snapshot nodes in event order.
+ * @param turnEnds - completed turn boundaries retained from the event window.
+ * @returns Message seq values whose visible position matches the fork boundary.
+ */
+export function messageBranchSeqs(
+  nodes: readonly ConversationNode[],
+  turnEnds: ReadonlyMap<number, number>,
+): ReadonlySet<number> {
+  const result = new Set<number>()
+  const boundaries = [...turnEnds].sort((a, b) => a[1] - b[1])
+  let nodeIndex = 0
+  for (const [turn, endSeq] of boundaries) {
+    let tail: ConversationNode | undefined
+    while (nodeIndex < nodes.length) {
+      const candidate = nodes[nodeIndex]
+      if (candidate === undefined || candidate.seq > endSeq) break
+      tail = candidate
+      nodeIndex++
+    }
+    if (tail?.kind === 'user'
+      || (tail?.kind === 'assistant' && tail.turn === turn && hasContentText(tail.blocks))) {
+      result.add(tail.seq)
+    }
+  }
+  return result
+}
+
 /**
 * Group finalized nodes into the step-summary flow.
 * @param nodes - snapshot nodes in human-transcript and durable-notice order.
@@ -454,7 +454,7 @@ export interface ChatViewInjected {
    /** Last recorded offset, or null when pinned or never recorded. */
    read: () => number | null
  }
-  /** Fork the session through the turn containing the message at `seq`, then open the child. */
+  /** Fork through the completed turn ending at the eligible message `seq`, then open the child. */
  forkAt: (seq: number) => void
 }

@@ -36,12 +36,14 @@ describe('MessageItem arms', () => {
    // Same-day clock: construct "today at 14:24" so the label stays `HH:mm`.
    const now = new Date()
    const time = new Date(now.getFullYear(), now.getMonth(), now.getDate(), 14, 24).getTime()
+    const onFork = vi.fn()
    render(
      <MessageItem t={t} node={{
        kind: 'user', seq: 1, time,
        content: [{ type: 'text', text: 'hello bubble' }] as never,
        source: null,
      }}
+      onFork={onFork}
      />,
    )
    expect(screen.getByText('14:24')).toBeTruthy()
@@ -50,6 +52,8 @@ describe('MessageItem arms', () => {
    expect(screen.queryByRole('button', { name: '编辑' })).toBeNull()
    fireEvent.click(screen.getByRole('button', { name: '复制' }))
    expect(writeText).toHaveBeenCalledWith('hello bubble')
+    fireEvent.click(screen.getByRole('button', { name: '在新对话中分支' }))
+    expect(onFork).toHaveBeenCalledWith(1)
  })

  it('user copy falls back to execCommand when clipboard.writeText is unavailable', () => {
@@ -410,12 +414,15 @@ describe('small branch tails', () => {
    })
    const now = new Date()
    const time = new Date(now.getFullYear(), now.getMonth(), now.getDate(), 14, 24).getTime()
+    const onFork = vi.fn()
    const settled = render(
      <AssistantMarkdown
        t={t}
        blocks={[{ kind: 'text', text: 'answer body' }, { kind: 'reasoning', text: 'hidden' }]}
        streaming={false}
        time={time}
+        seq={3}
+        onFork={onFork}
      />,
    )
    expect(settled.getByText('14:24')).toBeTruthy()
@@ -423,6 +430,8 @@ describe('small branch tails', () => {
    expect(settled.getByRole('button', { name: '在新对话中分支' })).toBeTruthy()
    fireEvent.click(settled.getByRole('button', { name: '复制' }))
    expect(writeText).toHaveBeenCalledWith('answer body')
+    fireEvent.click(settled.getByRole('button', { name: '在新对话中分支' }))
+    expect(onFork).toHaveBeenCalledWith(3)
    settled.unmount()

    const thinkOnly = render(
@@ -67,7 +67,7 @@ function snapshotWith(
  runningCalls: RunningToolCall[] = [],
 ): ConversationSnapshot {
  return {
-    sessionId: SID, nodes, partial: null, runningCalls, codeDispatches,
+    sessionId: SID, nodes, turnEnds: new Map(), partial: null, runningCalls, codeDispatches,
    pending: [], queue: [], running: runningCalls.length > 0, composerPhase: 'active', removed: false,
    openState: 'open', openError: null,
    hasMore: false, loadingOlder: false, promptError: null, blank: false, subagent: null, lastAgentError: null,
@@ -32,7 +32,7 @@ const assistant = (seq: number, turn: number, usage?: unknown): AssistantMessage

 function snapshotBase(): ConversationSnapshot {
  return {
-    sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+    sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
    hasMore: false, loadingOlder: false, promptError: null, blank: false, subagent: null, lastAgentError: null,
  }
@@ -20,7 +20,7 @@ import { zh as commonZh } from '@deepseek-ai/dsh-client-locale/src/locales/zh.ts
 import { createChatStore } from '../src/client/stores.ts'
 import { ChatView } from '../src/client/chat/ChatView.tsx'
 import { zh } from '../src/client/locales.ts'
-import { assistantActionsSeqs, deriveChatFlow, flowKeys } from '../src/client/chat/chat-flow.ts'
+import { assistantActionsSeqs, deriveChatFlow, flowKeys, messageBranchSeqs } from '../src/client/chat/chat-flow.ts'

 afterEach(cleanup)
 // Keyless create() persists under the bare declared key; clear between cases
@@ -33,7 +33,7 @@ const SID = 's1' as SessionId

 function snapshotBase(): ConversationSnapshot {
  return {
-    sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+    sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
    hasMore: false, loadingOlder: false, promptError: null, blank: false, subagent: null, lastAgentError: null,
  }
@@ -211,6 +211,24 @@ describe('chat-flow derivation', () => {
    ])
    expect([...seqs].sort((a, b) => a - b)).toEqual([5, 7])
  })
+
+  it('messageBranchSeqs keeps only message rows at completed transcript tails', () => {
+    const interruptedThink: AssistantMessageNode = {
+      kind: 'assistant', seq: 4.1, time: 4_100, turn: 1, step: 2,
+      blocks: [{ kind: 'reasoning', text: 'bad path' }], interrupted: true,
+    }
+    const nodes = [
+      user(1, 'first'),
+      assistant(2, 'answer before tools'),
+      toolResult(3, 'a'),
+      interruptedThink,
+      user(6, 'second'),
+      assistant(7, 'clean tail', 2),
+      user(10, 'user-only tail'),
+    ]
+    const seqs = messageBranchSeqs(nodes, new Map([[1, 5], [2, 8], [3, 11]]))
+    expect([...seqs]).toEqual([7, 10])
+  })
 })

 describe('ChatView', () => {
@@ -323,21 +341,38 @@ describe('ChatView', () => {
        user(5, 'next'),
        assistant(6, 'second turn', 2),
      ],
+      turnEnds: new Map([[1, 4], [2, 6]]),
    })
    const view = render(<h.ChatView {...h.props} />)
-    // 2 user + 2 turn-tail assistants; mid-turn text at seq 2 stays chrome-free.
+    // User rows keep copy/clock, while only the two completed assistant tails may branch.
    expect(view.getAllByRole('button', { name: '复制' })).toHaveLength(4)
-    expect(view.getAllByRole('button', { name: '在新对话中分支' })).toHaveLength(4)
+    expect(view.getAllByRole('button', { name: '在新对话中分支' })).toHaveLength(2)
  })

-  it('forks from both user and finalized assistant message actions at their event seq', () => {
-    const h = makeHarness({ nodes: [user(1, 'question'), assistant(2, 'answer')] })
+  it('forks only from a finalized assistant at the completed transcript tail', () => {
+    const h = makeHarness({
+      nodes: [user(1, 'question'), assistant(2, 'answer')],
+      turnEnds: new Map([[1, 3]]),
+    })
    const view = render(<h.ChatView {...h.props} />)
    const buttons = view.getAllByRole('button', { name: '在新对话中分支' })
-    expect(buttons).toHaveLength(2)
+    expect(buttons).toHaveLength(1)
    fireEvent.click(buttons[0]!)
-    fireEvent.click(buttons[1]!)
-    expect(h.forkAt.mock.calls).toEqual([[1], [2]])
+    expect(h.forkAt.mock.calls).toEqual([[2]])
+  })
+
+  it('keeps copy chrome but hides branch when tool and interrupted Think follow the response', () => {
+    const interruptedThink: AssistantMessageNode = {
+      kind: 'assistant', seq: 4.1, time: 4_100, turn: 1, step: 2,
+      blocks: [{ kind: 'reasoning', text: 'bad path' }], interrupted: true,
+    }
+    const h = makeHarness({
+      nodes: [user(1, 'question'), assistant(2, 'answer'), toolResult(3, 'a'), interruptedThink],
+      turnEnds: new Map([[1, 5]]),
+    })
+    const view = render(<h.ChatView {...h.props} />)
+    expect(view.getAllByRole('button', { name: '复制' })).toHaveLength(2)
+    expect(view.queryByRole('button', { name: '在新对话中分支' })).toBeNull()
  })

  it('renders assistant Markdown across history, streaming, final, and interrupted states while user text stays literal', () => {
@@ -335,7 +335,7 @@ describe('DetailsPanel diff Output section', () => {

  function snapshot(over: Partial<ConversationSnapshot> = {}): ConversationSnapshot {
    return {
-      sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+      sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
      pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
      openState: 'open', openError: null, hasMore: false, loadingOlder: false,
      promptError: null, blank: false, subagent: null, lastAgentError: null, ...over,
@@ -24,7 +24,7 @@ const SID = 's1' as SessionId

 function snapshotBase(): ConversationSnapshot {
  return {
-    sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+    sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
    hasMore: false, loadingOlder: false, promptError: null, blank: false, subagent: null, lastAgentError: null,
  }
@@ -23,7 +23,7 @@ const SID = 's1' as SessionId

 function snapshotOf(overrides: Partial<ConversationSnapshot> = {}): ConversationSnapshot {
  return {
-    sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+    sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
    openState: 'open', openError: null, hasMore: false, loadingOlder: false,
    promptError: null, blank: false, subagent: null, lastAgentError: null,
@@ -26,7 +26,7 @@ const SID = 's1' as SessionId
 /** Standard-props InputBar mount over a real shell (the composer-bar entry shape). */
 function mountBar(shell: SessionInputShell, over?: { running?: boolean; disabled?: boolean }) {
  const session = createSnapshotStore<ConversationSnapshot>({
-    sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+    sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: over?.running ?? false, composerPhase: 'active',
    removed: over?.disabled ?? false, openState: 'open', openError: null, hasMore: false,
    loadingOlder: false, promptError: null, blank: false, subagent: null, lastAgentError: null,
@@ -112,7 +112,7 @@ async function scopedBench(register?: (slash: SlashService) => void) {
  actx.on('slash/input-consume-token', req => shell.consumeToken(req.guard) ? true : undefined)
  const wiring = shell
  const sessionStore = createSnapshotStore<ConversationSnapshot>({
-    sessionId, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+    sessionId, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
    openState: 'open', openError: null, hasMore: false, loadingOlder: false,
    promptError: null, blank: false, subagent: null, lastAgentError: null,
@@ -28,7 +28,7 @@ function row(id: string, text: string | null, preview = text ?? '[image]'): Queu

 function snapshotWith(queue: QueuedMessage[]): ConversationSnapshot {
  return {
-    sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+    sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue, running: true, composerPhase: 'active', removed: false, openState: 'open', openError: null,
    hasMore: false, loadingOlder: false, promptError: null, blank: false, subagent: null, lastAgentError: null,
  }
@@ -283,7 +283,7 @@ describe('DetailsPanel Output section (read)', () => {

  function snapshot(over: Partial<ConversationSnapshot> = {}): ConversationSnapshot {
    return {
-      sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+      sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
      pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
      openState: 'open', openError: null, hasMore: false, loadingOlder: false,
      promptError: null, blank: false, subagent: null, lastAgentError: null, ...over,
@@ -397,7 +397,7 @@ describe('DetailsPanel Output section (search)', () => {

  function snapshot(over: Partial<ConversationSnapshot> = {}): ConversationSnapshot {
    return {
-      sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+      sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
      pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
      openState: 'open', openError: null, hasMore: false, loadingOlder: false,
      promptError: null, blank: false, subagent: null, lastAgentError: null, ...over,
@@ -68,7 +68,7 @@ const workspaceState = (items: readonly WorkspaceView[]): WorkspaceListState =>

 function conversationSnapshot(overrides: Partial<ConversationSnapshot> = {}): ConversationSnapshot {
  return {
-    sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+    sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
    openState: 'open', openError: null, hasMore: false, loadingOlder: false,
    promptError: null, blank: false, subagent: null, lastAgentError: null,
@@ -455,7 +455,7 @@ describe('DetailsPanel Output section', () => {

  function snapshot(over: Partial<ConversationSnapshot> = {}): ConversationSnapshot {
    return {
-      sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+      sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
      pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
      openState: 'open', openError: null, hasMore: false, loadingOlder: false,
      promptError: null, blank: false, subagent: null, lastAgentError: null, ...over,
@@ -232,7 +232,7 @@ describe('DetailsPanel web Output section', () => {

  function snapshot(over: Partial<ConversationSnapshot> = {}): ConversationSnapshot {
    return {
-      sessionId: SID, nodes: [], partial: null, runningCalls: [], codeDispatches: new Map(),
+      sessionId: SID, nodes: [], turnEnds: new Map(), partial: null, runningCalls: [], codeDispatches: new Map(),
      pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
      openState: 'open', openError: null, hasMore: false, loadingOlder: false,
      promptError: null, blank: false, subagent: null, lastAgentError: null, ...over,