Merge remote-tracking branch 'origin/master' into worktree/web-skill-tool-row

# Conflicts: # apps/web/tsconfig.json # tsconfig.host.json
2026-08-07 12:48:08 +08:00
parent 3aa3212fd7 079d71d591
commit 9264f383e6
60 changed files with 1154 additions and 213 deletions
--- a/packages/client/ui-conversation/README.i18n.yaml
+++ b/packages/client/ui-conversation/README.i18n.yaml
@@ -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: 8d6c26f67916f043251c58a3283542bd58a08666
-README.zh.md: 8dd43cca59f8dfda18ce036b5d8c6f948306c947
+README.md: a75f25d8669cd688795842a655106e0e27bb7173
+README.zh.md: f0d744c31020730857d210d75749b907dbffca08
--- a/packages/client/ui-conversation/README.md
+++ b/packages/client/ui-conversation/README.md
@@ -38,7 +38,7 @@ The todo surfaces are two registrations over that shape, both using slot declara

 `QueueDock` is the terminal input-dock entry at `order: 20`. It hides while empty, renders one pending row directly, and defaults two or more rows to a collapsed `"<n> 条排队消息"` header whose button expands or collapses the complete list. The header exposes `aria-expanded` and `aria-controls`; the expanded list scrolls within a 180px height bound. An active edit or mutation keeps its rows visible, and emptying the queue restores the collapsed default for the next queue. Each visible ordinary-session row remains a single-line preview with its exact-occurrence edit, delete, and strict-steer actions; addressed subagents retain the rows as a read-only projection because their continuation transport does not expose queue mutation. If strict steer loses to a closed window, the original occurrence remains queued for normal delivery; if the driver already claimed it, normal delivery is already underway. Neither converged race displays a failure, while transport and unknown failures do.

-The Host's placement-aware `session/queue` snapshot also carries pending steering. QueueDock filters it out, while ChatView projects it as a user-style bubble with Copy at the conversation tail; non-user next-step items (injected context) carry the `context` placement instead and render nowhere until claimed. Fork stays absent because the message has not entered a durable turn. The Host delays steering retirement until the durable `user/message` carrying the steering has entered the mux stream. On that accepted live event, the client runtime retires the first matching current steering occurrence before publishing the snapshot; historical events cannot hide later occurrences that reuse the same `MessageId`. The bubble therefore hands off without a gap or duplicate, immediately restores Copy and the branch control from the durable node, enables branch only when that node is the completed turn's transcript tail, and survives reconnect from the same authority.
+The Host's placement-aware `session/queue` snapshot also carries pending steering. QueueDock filters it out, while ChatView projects it as a user-style bubble with Copy at the conversation tail; non-user next-step items (injected context) carry the `context` placement instead and render nowhere until claimed. Fork is absent here as on every user-style bubble. The Host delays steering retirement until the durable `user/message` carrying the steering has entered the mux stream. On that accepted live event, the client runtime retires the first matching current steering occurrence before publishing the snapshot; historical events cannot hide later occurrences that reuse the same `MessageId`. The bubble therefore hands off without a gap or duplicate, immediately restores Copy and the clock from the durable node — a steering bubble, like a user bubble, carries no branch action ([decision](../../../.agents/notes/implemented/simplification/2026-08-06-user-bubbles-drop-the-branch-action.md)) — and survives reconnect from the same authority.

 Keyboard message submission resolves delivery from the addressed session's running state and steering capability. While idle, Enter and Cmd/Ctrl+Enter both perform an ordinary Queue send. While a primary session is running, the browser-persisted General Settings preference assigns plain Enter to `Queue` (the default) or `Steer`, and Cmd/Ctrl+Enter performs the other behavior; Shift+Enter remains a newline. Addressed subagents keep both gestures on their Queue-only continuation transport even while running. The preference affects only the steer-capable busy-state gesture pair, and the send button and non-keyboard submit actions remain Queue. Composer Steer uses the existing best-effort `session.prompt(mode: 'steer')` contract: if the current next-step window closes before acceptance, AgentLoop admits the message as the next waking Queue turn without surfacing a failure or losing the draft transaction.

@@ -63,8 +63,8 @@ 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 and speeds cover the in-window flow only** — LLM and tool wall times plus the TTFT and throughput averages fold the snapshot's assistant `timing` and tool call/result pairs, so nodes outside the loaded event window (older history) are not counted.
 - **The details panel has no entry point** — `ChatViewInjected.openDetails` is implemented but uncalled, so the raw selected-call display is unreachable in the assembled application. There is no Input/Output/Metadata switch, Prev/Next stepping, or trajectory deep link.
- **Assistant per-message paging is a reserved slot** — drawn in the design, not implemented. The finalized content IconActions row (copy / clock / branch) ships under the last content-text assistant of each turn only; mid-turn narration and Think-only nodes stay chrome-free. Branch stays disabled unless that message is also the last transcript node of a completed turn; when enabled, it 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, copy, and branch; branch stays disabled unless a completed turn's 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)).
+- **Assistant per-message paging is a reserved slot** — drawn in the design, not implemented. The finalized content IconActions row (copy / clock / branch) ships under the last content-text assistant of each turn that has ended; mid-turn narration, Think-only nodes, and every node of a turn still producing steps stay chrome-free. Branch stays disabled unless that message is also the last transcript node of a completed turn; when enabled, it 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; branch lives only under assistant answers ([decision](../../../.agents/notes/implemented/simplification/2026-08-06-user-bubbles-drop-the-branch-action.md)). 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 has no durable grant control** — it supports allow-once and reject only.
 - **TodoPanel truncates long item text to one ellipsized line** — the figma strip has no wrap or expand affordance; full text is not readable inline.
--- a/packages/client/ui-conversation/README.zh.md
+++ b/packages/client/ui-conversation/README.zh.md
@@ -38,7 +38,7 @@ todo 两个面就是在该形状上的两个注册项，都使用 slot 声明注

 `QueueDock` 是 `order: 20` 的末端 input-dock 条目。队列为空时隐藏；只有一个待处理项时直接渲染该行；存在两个或更多待处理项时，默认收起为 `"<n> 条排队消息"` 表头，其按钮可展开或收起完整列表。表头暴露 `aria-expanded` 和 `aria-controls`；展开后的列表以 180px 为高度上限，并可滚动。存在进行中的编辑或变更时，列表行会保持可见；队列清空后，下一次出现队列时会恢复默认收起状态。普通会话中的每条可见行仍是单行预览，并提供针对精确单次入队项的编辑、删除和严格 steering 操作；已寻址 subagent 则保留只读行，因为其继续执行传输不提供 Queue 变更。如果严格 steering 输给已关闭的窗口，原单次入队项会留在 Queue 中正常投递；如果驱动器已经认领该项，正常投递就已开始。这两种已收敛的竞态都不显示失败，传输和未知错误仍会显示。

-Host 带 placement 的 `session/queue` 快照也会携带待处理 steering。QueueDock 会将其过滤掉，ChatView 则把它投影为会话流末尾带复制操作的用户样式气泡；非用户来源的 next-step 项（注入上下文）改以 `context` placement 广播，领取前不在任何界面渲染。消息尚未进入持久轮次，因此不显示 fork。Host 会等携带该 steering 的持久 `user/message` 进入 mux 流之后再退役 steering。客户端运行时接纳该实时事件时，会在发布快照前退役第一个匹配的当前 steering 单次入队项；历史事件无法隐藏后来复用同一 `MessageId` 的单次入队项。气泡交接时因而不会产生空档或重复，会立即从持久节点恢复复制操作与分支控件，仅当该节点是已完成轮次的 transcript 尾部时才启用分支，并能在重连后从同一权威恢复。
+Host 带 placement 的 `session/queue` 快照也会携带待处理 steering。QueueDock 会将其过滤掉，ChatView 则把它投影为会话流末尾带复制操作的用户样式气泡；非用户来源的 next-step 项（注入上下文）改以 `context` placement 广播，领取前不在任何界面渲染。与所有用户样式气泡一样，这里不显示 fork。Host 会等携带该 steering 的持久 `user/message` 进入 mux 流之后再退役 steering。客户端运行时接纳该实时事件时，会在发布快照前退役第一个匹配的当前 steering 单次入队项；历史事件无法隐藏后来复用同一 `MessageId` 的单次入队项。气泡交接时因而不会产生空档或重复，会立即从持久节点恢复复制操作与时钟——steering 气泡与 user 气泡一样不带分支操作（[决策](../../../.agents/notes/implemented/simplification/2026-08-06-user-bubbles-drop-the-branch-action.md)）——并能在重连后从同一权威恢复。

 键盘消息提交会根据所寻址会话的运行状态和 steering 能力解析投递方式。空闲时，Enter 和 Cmd/Ctrl+Enter 都执行普通 Queue 发送。主会话运行期间，浏览器持久化的 General Settings 偏好会把普通 Enter 分配为 `Queue`（默认值）或 `Steer`，Cmd/Ctrl+Enter 则执行另一种行为；Shift+Enter 仍然换行。已寻址 subagent 即使正在运行，也会让这两个手势都使用其仅支持 Queue 的继续执行传输。该偏好只影响支持 steering 的繁忙态手势对，发送按钮与非键盘提交操作仍使用 Queue。Composer Steer 复用现有尽力而为的 `session.prompt(mode: 'steer')` 契约：如果当前 next-step 窗口在接纳前关闭，AgentLoop 会把消息接纳为下一条唤醒 Queue 轮次，不显示失败，也不会丢失草稿事务。

@@ -63,8 +63,8 @@ Host 带 placement 的 `session/queue` 快照也会携带待处理 steering。Qu
 - **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。
 - **统计行的耗时与速率只覆盖窗口内消息流**：LLM 与工具墙钟时间以及 TTFT 与吞吐平均值由快照的 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。
 - **详情面板没有入口**：`ChatViewInjected.openDetails` 虽已实现却无人调用，因此以原始形式显示已选择调用的那部分在组装后的应用中不可达。没有 Input/Output/Metadata 切换、Prev/Next 步进，也没有 trajectory 深链接。
- **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／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。除非该消息同时也是已完成轮次的最后一个 transcript 节点，否则分支保持禁用；启用后，它会 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、复制和分支；除非已完成轮次的 transcript 结束于该 user 消息，否则分支保持禁用。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)）。
+- **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／分支）只挂在每个已结束轮次中最后一条带 text 内容的 assistant 下；轮次中间的叙述、纯 Think 节点，以及仍在产出步骤的轮次里的所有节点都不带 chrome。除非该消息同时也是已完成轮次的最后一个 transcript 节点，否则分支保持禁用；启用后，它会 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；分支只存在于 assistant 回答之下（[决策](../../../.agents/notes/implemented/simplification/2026-08-06-user-bubbles-drop-the-branch-action.md)）。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。
--- a/packages/client/ui-conversation/src/client/chat/AssistantMarkdown.tsx
+++ b/packages/client/ui-conversation/src/client/chat/AssistantMarkdown.tsx
@@ -4,10 +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 content (text) nodes append IconActions once streaming ends
-// (`time` is omitted for mid-turn narration); their branch action is enabled
-// only when the node is also the completed turn's transcript tail. Think /
-// tool-head-only nodes stay chrome-free.
+// Finalized content (text) nodes append IconActions once their turn ends
+// (`time` is omitted for mid-turn narration and while the turn still runs);
+// their branch action is enabled 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'
@@ -15,6 +15,7 @@ import {
  IconThinkOutline14, JsonBlock, MarkdownText,
 } from '@deepseek-ai/dsh-client-ui-primitives'
 import type { ChatViewSlotProps } from '../contract/slots.ts'
+import { hasContentText } from './chat-flow.ts'
 import { MessageIconActions } from './MessageIconActions.tsx'
 import { ToolRow } from './ToolRow.tsx'
 import css from './AssistantMarkdown.module.css'
@@ -25,7 +26,8 @@ export interface AssistantMarkdownProps {
  /** Frozen partial of an aborted turn: rendered with a stopped marker. */
  interrupted?: boolean | undefined
  /** Unix epoch ms for the IconActions clock; omitted while streaming or when
-   *  the parent withholds chrome (mid-turn content assistants). */
+   *  the parent withholds chrome (mid-turn content assistants and every node
+   *  of a turn that has not ended). */
  time?: number | undefined
  /** Turn wall time in ms for the IconActions run-time label; omitted when the
   *  turn's triggering input is outside the loaded window. */
@@ -65,11 +67,6 @@ function copyText(blocks: readonly AssistantBlock[]): string {
  return parts.join('')
 }

-/** True when the node has model-visible text content worth chrome under. */
-function hasContentText(blocks: readonly AssistantBlock[]): boolean {
-  return blocks.some(block => block.kind === 'text' && block.text.trim() !== '')
-}
-
 /** Reasoning block as the Think variant summary row (figma 39:28304). */
 function ThinkRow({ text, running, t }: { text: string; running: boolean; t: AssistantMarkdownProps['t'] }) {
  return (
--- a/packages/client/ui-conversation/src/client/chat/ChatView.tsx
+++ b/packages/client/ui-conversation/src/client/chat/ChatView.tsx
@@ -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, messageBranchSeqs, runningTurnStartTime, type ChatFlowItem } from './chat-flow.ts'
+import { assistantActionsSeqs, assistantBranchSeqs, deriveChatFlow, runningTurnStartTime, type ChatFlowItem } from './chat-flow.ts'
 import { AssistantMarkdown } from './AssistantMarkdown.tsx'
 import { GenericCommandCard } from './GenericCommandCard.tsx'
 import { GenericToolCard } from './GenericToolCard.tsx'
@@ -358,10 +358,11 @@ export function ChatView({
    [inbox],
  )
  const activeRetry = useMemo(() => activeRetrySeq(nodes, running), [nodes, running])
-  // 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])
+  // Only the last content assistant of each completed turn owns IconActions;
+  // mid-turn text and every node of a running turn omit `time`, so
+  // AssistantMarkdown stays chrome-free until the answer settles.
+  const actionSeqs = useMemo(() => assistantActionsSeqs(nodes, turnEnds), [nodes, turnEnds])
+  const branchSeqs = useMemo(() => assistantBranchSeqs(nodes, turnEnds), [nodes, turnEnds])
  const runningTurnStart = useMemo(() => runningTurnStartTime(turnTimings), [turnTimings])
  const turnMetrics = useMemo(() => deriveTurnMetrics(nodes), [nodes])

@@ -631,8 +632,6 @@ export function ChatView({
      <MessageItem
        node={node}
        retryActive={node.kind === 'model-retry' && node.seq === activeRetry}
-        onFork={forkAt}
-        forkUnavailable={!branchSeqs.has(node.seq)}
        t={t}
      />
    )
--- a/packages/client/ui-conversation/src/client/chat/MessageIconActions.tsx
+++ b/packages/client/ui-conversation/src/client/chat/MessageIconActions.tsx
@@ -27,8 +27,6 @@ export interface MessageIconActionsProps {
  onBranch?: (() => void) | undefined
  /** The message is not a completed transcript tail, so branch stays visible but unavailable. */
  branchUnavailable?: boolean | undefined
-  /** Additional branch visibility gate for transient message chrome; defaults to true. */
-  showBranch?: boolean | undefined
  /** Parent layout class composed onto the actions row. */
  className?: string | undefined
  /** The owning view's locale seat, passed down as a plain prop. */
@@ -41,7 +39,7 @@ export interface MessageIconActionsProps {
 * @returns The actions row element.
 */
 export function MessageIconActions({
-  text, time, runMs, ttftMs, tokensPerSecond, clock, onBranch, branchUnavailable = false, showBranch = true, className, t,
+  text, time, runMs, ttftMs, tokensPerSecond, clock, onBranch, branchUnavailable = false, className, t,
 }: MessageIconActionsProps) {
  const day = useCalendarDay()
  const reasonId = useId()
@@ -111,7 +109,7 @@ export function MessageIconActions({
          {copied ? <IconCheckOutline16 /> : <IconCopyOutline16 />}
        </button>
      </Tooltip>
-      {showBranch && onBranch !== undefined && (
+      {onBranch !== undefined && (
        <Tooltip label={branchUnavailable ? t('message.branchUnavailable') : t('message.branch')} side="bottom">
          {/* Native disabled buttons do not deliver the hover/focus events Tooltip needs. */}
          <button
@@ -127,7 +125,7 @@ export function MessageIconActions({
          </button>
        </Tooltip>
      )}
-      {showBranch && onBranch !== undefined && branchUnavailable && (
+      {onBranch !== undefined && branchUnavailable && (
        <span id={reasonId} className={css.visuallyHidden}>{t('message.branchUnavailable')}</span>
      )}
      {clock === 'end' ? clockEl : null}
--- a/packages/client/ui-conversation/src/client/chat/MessageItem.tsx
+++ b/packages/client/ui-conversation/src/client/chat/MessageItem.tsx
@@ -1,8 +1,8 @@
 // MessageItem: simple chat nodes — user and consumed-steering bubbles
-// (right-aligned, with clock + copy / branch IconActions; steering adds the
-// interjection caption that names it), pending steering (caption + copy only),
-// context injection, compaction marker, retry disclosure, and unknown-surface
-// JSON rows.
+// (right-aligned, with clock + copy IconActions; steering adds the
+// interjection caption that names it; branch lives only under assistant
+// answers), pending steering (caption + copy only), context injection,
+// compaction marker, retry disclosure, and unknown-surface JSON rows.

 import { memo, useEffect, useMemo, useState } from 'react'
 import type { ReactNode } from 'react'
@@ -27,10 +27,6 @@ export interface MessageItemProps {
    | TurnErrorNode
    | UnknownSurfaceNode
  retryActive?: boolean
-  /** Fork through this message's completed turn when eligible. */
-  onFork?: (seq: number) => void
-  /** The message is not the transcript tail of a completed turn. */
-  forkUnavailable?: boolean
  /** The owning view's locale seat, passed down as a plain prop. */
  t: ChatViewSlotProps['t']
 }
@@ -217,7 +213,6 @@ export function PendingSteeringBubble({ content, t }: {
        <MessageIconActions
          text={text}
          clock="start"
-          showBranch={false}
          className={css.actions}
          t={t}
        />
@@ -227,7 +222,7 @@ export function PendingSteeringBubble({ content, t }: {
 }

 export const MessageItem = memo(function MessageItem({
-  node, retryActive = false, onFork, forkUnavailable = false, t,
+  node, retryActive = false, t,
 }: MessageItemProps) {
  const truncated = (total: number): string => t('json.truncated', { total })
  switch (node.kind) {
@@ -243,8 +238,6 @@ export const MessageItem = memo(function MessageItem({
              text={text}
              time={node.time}
              clock="start"
-              onBranch={onFork === undefined ? undefined : () => { onFork(node.seq) }}
-              branchUnavailable={forkUnavailable}
              className={css.actions}
              t={t}
            />
--- a/packages/client/ui-conversation/src/client/chat/chat-flow.ts
+++ b/packages/client/ui-conversation/src/client/chat/chat-flow.ts
@@ -17,8 +17,14 @@ export type ChatFlowItem =
  | { kind: 'node'; key: string; node: ConversationNode }
  | { kind: 'tool-group'; key: string; results: readonly ToolResultNode[] }

-/** True when the node has model-visible text content worth IconActions chrome. */
-function hasContentText(blocks: readonly AssistantBlock[]): boolean {
+/**
+ * True when the node has model-visible text content worth IconActions chrome.
+ * Shared with {@link AssistantMarkdown}'s mount gate so ownership and mounting
+ * cannot diverge.
+ * @param blocks - assistant blocks of one finalized node.
+ * @returns Whether any text block carries non-blank content.
+ */
+export function hasContentText(blocks: readonly AssistantBlock[]): boolean {
  return blocks.some(block => block.kind === 'text' && block.text.trim() !== '')
 }

@@ -34,14 +40,20 @@ function rendersNothing(node: ConversationNode): boolean {

 /**
 * Seq set of assistants that own IconActions: the last content-text assistant
- * in each turn. Mid-turn narration (text before tools) stays chrome-free.
+ * of each *completed* turn. A turn without a `turn/end` in the window is still
+ * producing steps, so its latest narration is not the settled answer and owns
+ * nothing; mid-turn narration of a completed turn stays chrome-free too.
 * @param nodes - snapshot nodes (surface order).
+ * @param turnEnds - completed turn boundaries retained from the event window.
 * @returns Seq values ChatView may pass as `time` into AssistantMarkdown.
 */
-export function assistantActionsSeqs(nodes: readonly ConversationNode[]): ReadonlySet<number> {
+export function assistantActionsSeqs(
+  nodes: readonly ConversationNode[],
+  turnEnds: ReadonlyMap<number, number>,
+): ReadonlySet<number> {
  const lastByTurn = new Map<number, number>()
  for (const node of nodes) {
-    if (node.kind !== 'assistant' || !hasContentText(node.blocks)) continue
+    if (node.kind !== 'assistant' || !turnEnds.has(node.turn) || !hasContentText(node.blocks)) continue
    lastByTurn.set(node.turn, node.seq)
  }
  return new Set(lastByTurn.values())
@@ -63,15 +75,18 @@ export function runningTurnStartTime(
 }

 /**
- * 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 leaves the earlier message's branch action
- * unavailable because the Host would include the whole turn.
+ * Seq set of assistant answers that may fork: the completed turn's transcript
+ * tail, when that tail is the turn's own content-text assistant. A later tool,
+ * reasoning, error, or other transcript node leaves the answer's branch action
+ * unavailable because the Host would include the whole turn. User and steering
+ * bubbles carry no branch action at all: a fork at their seq cuts at the same
+ * `turn/end` as the answer's, so the affordance lives only under the settled
+ * answer.
 * @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.
+ * @returns Assistant seq values whose visible position matches the fork boundary.
 */
-export function messageBranchSeqs(
+export function assistantBranchSeqs(
  nodes: readonly ConversationNode[],
  turnEnds: ReadonlyMap<number, number>,
 ): ReadonlySet<number> {
@@ -86,8 +101,7 @@ export function messageBranchSeqs(
      tail = candidate
      nodeIndex++
    }
-    if (tail?.kind === 'user' || tail?.kind === 'steering'
-      || (tail?.kind === 'assistant' && tail.turn === turn && hasContentText(tail.blocks))) {
+    if (tail?.kind === 'assistant' && tail.turn === turn && hasContentText(tail.blocks)) {
      result.add(tail.seq)
    }
  }
--- a/packages/client/ui-conversation/tests/chat-branch-tails.spec.tsx
+++ b/packages/client/ui-conversation/tests/chat-branch-tails.spec.tsx
@@ -36,7 +36,7 @@ afterEach(() => {
 const t: MessageItemProps['t'] = makeTranslate(zh, commonZh)

 describe('MessageItem arms', () => {
-  it('user bubbles expose clock / copy / branch and no edit; copy writes the text', () => {
+  it('user bubbles expose clock / copy and neither branch nor edit; copy writes the text', () => {
    const writeText = vi.fn().mockResolvedValue(undefined)
    Object.defineProperty(navigator, 'clipboard', {
      configurable: true,
@@ -45,24 +45,20 @@ 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()
    expect(screen.getByRole('button', { name: '复制' })).toBeTruthy()
-    expect(screen.getByRole('button', { name: '在新对话中分支' })).toBeTruthy()
+    expect(screen.queryByRole('button', { name: '在新对话中分支' })).toBeNull()
    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', () => {
@@ -87,30 +83,6 @@ describe('MessageItem arms', () => {
    expect(exec).toHaveBeenCalledWith('copy')
  })

-  it('keeps an unavailable branch focusable and explains why without sending a fork', () => {
-    const onFork = vi.fn()
-    render(
-      <MessageItem t={t} node={{
-        kind: 'user', seq: 1, time: 1_000,
-        content: [{ type: 'text', text: 'open turn' }] as never,
-        source: null,
-      }}
-      onFork={onFork}
-      forkUnavailable
-      />,
-    )
-    const branch = screen.getByRole('button', { name: '在新对话中分支' }) as HTMLButtonElement
-    expect(branch.disabled).toBe(false)
-    expect(branch.getAttribute('aria-disabled')).toBe('true')
-    const reasonId = branch.getAttribute('aria-describedby')
-    expect(reasonId).not.toBeNull()
-    expect(document.getElementById(reasonId!)?.textContent).toBe('仅可从已完成轮次的最后一条消息分支')
-    fireEvent.click(branch)
-    expect(onFork).not.toHaveBeenCalled()
-    fireEvent.focus(branch)
-    expect(screen.getByRole('tooltip').textContent).toBe('仅可从已完成轮次的最后一条消息分支')
-  })
-
  it('user copy never claims success when the host rejects the write', async () => {
    Object.defineProperty(navigator, 'clipboard', {
      configurable: true,
@@ -212,19 +184,17 @@ describe('MessageItem arms', () => {
    expect(vi.getTimerCount()).toBe(0)
  })

-  it('consumed steering is captioned as an interjection and keeps copy and branch actions', () => {
+  it('consumed steering is captioned as an interjection and keeps copy without branch', () => {
    const writeText = vi.fn().mockResolvedValue(undefined)
    Object.defineProperty(navigator, 'clipboard', {
      configurable: true,
      value: { writeText },
    })
-    const fork = vi.fn()
    const view = render(
      <MessageItem t={t} node={{
        kind: 'steering', messageId: 'steer-message', seq: 2, time: 1_000, turn: 1, source: null,
        content: [{ type: 'text', text: 'steer!' }, { type: 'image', data: 'x' }] as never,
      } as never}
-      onFork={fork}
      />,
    )
    expect(view.getByText('插话')).toBeTruthy()
@@ -232,8 +202,7 @@ describe('MessageItem arms', () => {
    expect(view.getByText(/附加内容块/)).toBeTruthy()
    fireEvent.click(view.getByRole('button', { name: '复制' }))
    expect(writeText).toHaveBeenCalledWith('steer!')
-    fireEvent.click(view.getByRole('button', { name: '在新对话中分支' }))
-    expect(fork).toHaveBeenCalledWith(2)
+    expect(view.queryByRole('button', { name: '在新对话中分支' })).toBeNull()
  })

  it('context uses the Tool calls disclosure chrome and keeps its body collapsed by default', () => {
@@ -1002,6 +971,31 @@ describe('small branch tails', () => {
    expect(streaming.queryByText('14:24')).toBeNull()
  })

+  it('keeps an unavailable branch focusable and explains why without sending a fork', () => {
+    const onFork = vi.fn()
+    render(
+      <AssistantMarkdown
+        t={t}
+        blocks={[{ kind: 'text', text: 'answer before a trailing tool row' }]}
+        streaming={false}
+        time={1_000}
+        seq={1}
+        onFork={onFork}
+        forkUnavailable
+      />,
+    )
+    const branch = screen.getByRole('button', { name: '在新对话中分支' }) as HTMLButtonElement
+    expect(branch.disabled).toBe(false)
+    expect(branch.getAttribute('aria-disabled')).toBe('true')
+    const reasonId = branch.getAttribute('aria-describedby')
+    expect(reasonId).not.toBeNull()
+    expect(document.getElementById(reasonId!)?.textContent).toBe('仅可从已完成轮次的最后一条消息分支')
+    fireEvent.click(branch)
+    expect(onFork).not.toHaveBeenCalled()
+    fireEvent.focus(branch)
+    expect(screen.getByRole('tooltip').textContent).toBe('仅可从已完成轮次的最后一条消息分支')
+  })
+
  it('StatsLine omits the cache-hit segment when no input accounting exists at all', () => {
    // Cache hit is null only when all three prompt buckets are zero (pure
    // output accounting) — any billed input makes it a real 0%.
--- a/packages/client/ui-conversation/tests/chat-view.spec.tsx
+++ b/packages/client/ui-conversation/tests/chat-view.spec.tsx
@@ -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, messageBranchSeqs, runningTurnStartTime } from '../src/client/chat/chat-flow.ts'
+import { assistantActionsSeqs, assistantBranchSeqs, deriveChatFlow, flowKeys, runningTurnStartTime } from '../src/client/chat/chat-flow.ts'
 import { formatRunDuration } from '../src/client/chat/message-chrome.ts'

 afterEach(() => {
@@ -225,12 +225,12 @@ describe('chat-flow derivation', () => {
    expect(flowKeys(deriveChatFlow([toolResult(3, 'a'), assistant(4, 'found'), toolResult(5, 'b')]))).toBe('g3|n4|g5')
  })

-  it('assistantActionsSeqs keeps only the last content assistant per turn', () => {
+  it('assistantActionsSeqs keeps only the last content assistant per completed turn', () => {
    const thinkOnly: AssistantMessageNode = {
      kind: 'assistant', seq: 3, time: 3_000, turn: 1, step: 2,
      blocks: [{ kind: 'reasoning', text: 'planning' }],
    }
-    const seqs = assistantActionsSeqs([
+    const nodes: ConversationNode[] = [
      user(1, 'hi'),
      assistant(2, 'looking', 1),
      thinkOnly,
@@ -238,8 +238,11 @@ describe('chat-flow derivation', () => {
      assistant(5, 'done', 1),
      user(6, 'again'),
      assistant(7, 'second turn', 2),
-    ])
-    expect([...seqs].sort((a, b) => a - b)).toEqual([5, 7])
+    ]
+    expect([...assistantActionsSeqs(nodes, new Map([[1, 5], [2, 7]]))].sort((a, b) => a - b)).toEqual([5, 7])
+    // Turn 2 is still producing steps: its latest narration owns nothing, and
+    // the settled turn 1 keeps its seat.
+    expect([...assistantActionsSeqs(nodes, new Map([[1, 5]]))]).toEqual([5])
  })

  it('runningTurnStartTime selects the latest turn/start without a turn/end', () => {
@@ -261,7 +264,7 @@ describe('chat-flow derivation', () => {
    expect(formatRunDuration(125_000, t)).toBe('2分05秒')
  })

-  it('messageBranchSeqs keeps only message rows at completed transcript tails', () => {
+  it('assistantBranchSeqs keeps only content-assistant tails; user/steering tails own no branch', () => {
    const interruptedThink: AssistantMessageNode = {
      kind: 'assistant', seq: 4.1, time: 4_100, turn: 1, step: 2,
      blocks: [{ kind: 'reasoning', text: 'bad path' }], interrupted: true,
@@ -276,8 +279,8 @@ describe('chat-flow derivation', () => {
      user(10, 'user-only tail'),
      user(13, 'steering tail'),
    ]
-    const seqs = messageBranchSeqs(nodes, new Map([[1, 5], [2, 8], [3, 11], [4, 14]]))
-    expect([...seqs]).toEqual([7, 10, 13])
+    const seqs = assistantBranchSeqs(nodes, new Map([[1, 5], [2, 8], [3, 11], [4, 14]]))
+    expect([...seqs]).toEqual([7])
  })
 })

@@ -401,21 +404,24 @@ describe('ChatView', () => {
    expect(view.getAllByText('interrupt now')).toHaveLength(1)
    expect(view.container.querySelector('[data-pending-steering]')).toBeNull()
    expect(view.getAllByText('插话')).toHaveLength(1)
-    expect(view.getAllByRole('button', { name: '复制' })).toHaveLength(2)
+    // Only the durable steering bubble: the turn is still running, so its
+    // assistant narration owns no footer yet, and a steering bubble never
+    // carries a branch action.
+    expect(view.getAllByRole('button', { name: '复制' })).toHaveLength(1)
    const durableBubble = view.getByText('interrupt now').closest('[class*="userRow"]') as HTMLElement
-    const unavailable = within(durableBubble).getByRole('button', { name: '在新对话中分支' })
-    expect(unavailable.getAttribute('aria-disabled')).toBe('true')
-    fireEvent.click(unavailable)
-    expect(h.forkAt).not.toHaveBeenCalled()
+    expect(within(durableBubble).queryByRole('button', { name: '在新对话中分支' })).toBeNull()

    act(() => {
      h.set({ running: false, turnEnds: new Map([[1, 3]]) })
    })
+    // The completed turn's transcript tail is the steering bubble, not the
+    // narration, so the assistant's branch action stays unavailable and the
+    // steering bubble still offers none.
    const branchButtons = view.getAllByRole('button', { name: '在新对话中分支' })
-    expect(branchButtons).toHaveLength(2)
-    expect(branchButtons.map(button => button.getAttribute('aria-disabled'))).toEqual(['true', null])
-    fireEvent.click(branchButtons[1]!)
-    expect(h.forkAt).toHaveBeenCalledWith(2)
+    expect(branchButtons).toHaveLength(1)
+    expect(branchButtons[0]!.getAttribute('aria-disabled')).toBe('true')
+    fireEvent.click(branchButtons[0]!)
+    expect(h.forkAt).not.toHaveBeenCalled()
  })

  it('keeps a later pending occurrence visible when it reuses a durable MessageId', () => {
@@ -518,11 +524,35 @@ describe('ChatView', () => {
      turnEnds: new Map([[1, 4], [2, 6]]),
    })
    const view = render(<h.ChatView {...h.props} />)
-    // Every message footer keeps branch visible; only completed assistant tails enable it.
+    // Branch renders only under assistant answers; user bubbles keep copy alone.
    expect(view.getAllByRole('button', { name: '复制' })).toHaveLength(4)
    const branchButtons = view.getAllByRole('button', { name: '在新对话中分支' })
-    expect(branchButtons).toHaveLength(4)
-    expect(branchButtons.map(button => button.getAttribute('aria-disabled'))).toEqual(['true', null, 'true', null])
+    expect(branchButtons).toHaveLength(2)
+    expect(branchButtons.map(button => button.getAttribute('aria-disabled'))).toEqual([null, null])
+  })
+
+  it('withholds assistant IconActions while the turn is still running', () => {
+    const h = makeHarness({
+      running: true,
+      runningCalls: [runningCall('a')],
+      nodes: [
+        user(1, 'first'),
+        assistant(2, 'previous answer', 1),
+        user(4, 'second'),
+        assistant(5, 'mid-turn text', 2),
+      ],
+      // Boundary seqs follow the log: a turn/end is strictly after its own nodes.
+      turnEnds: new Map([[1, 3]]),
+    })
+    const view = render(<h.ChatView {...h.props} />)
+    // 2 user + the settled turn-1 tail, which keeps its seat while a later
+    // turn runs; turn 2's narration stays chrome-free while its tool runs, so
+    // the footer never appears and then moves.
+    expect(view.getAllByRole('button', { name: '复制' })).toHaveLength(3)
+    expect(view.getByText('mid-turn text')).toBeTruthy()
+    // turn/end lands: the same node becomes the settled answer and takes the seat.
+    act(() => { h.set({ running: false, runningCalls: [], turnEnds: new Map([[1, 3], [2, 6]]) }) })
+    expect(view.getAllByRole('button', { name: '复制' })).toHaveLength(4)
  })

  it('the actions-owning assistant footer shows the turn run time', () => {
@@ -606,11 +636,11 @@ describe('ChatView', () => {
      turnEnds: new Map([[1, 3]]),
    })
    const view = render(<h.ChatView {...h.props} />)
+    // The user bubble offers no branch; the settled answer's is live.
    const buttons = view.getAllByRole('button', { name: '在新对话中分支' })
-    expect(buttons).toHaveLength(2)
-    expect(buttons.map(button => button.getAttribute('aria-disabled'))).toEqual(['true', null])
+    expect(buttons).toHaveLength(1)
+    expect(buttons[0]!.getAttribute('aria-disabled')).toBeNull()
    fireEvent.click(buttons[0]!)
-    fireEvent.click(buttons[1]!)
    expect(h.forkAt.mock.calls).toEqual([[2]])
  })

@@ -626,10 +656,9 @@ describe('ChatView', () => {
    const view = render(<h.ChatView {...h.props} />)
    expect(view.getAllByRole('button', { name: '复制' })).toHaveLength(2)
    const buttons = view.getAllByRole('button', { name: '在新对话中分支' })
-    expect(buttons).toHaveLength(2)
-    expect(buttons.every(button => button.getAttribute('aria-disabled') === 'true')).toBe(true)
+    expect(buttons).toHaveLength(1)
+    expect(buttons[0]!.getAttribute('aria-disabled')).toBe('true')
    fireEvent.click(buttons[0]!)
-    fireEvent.click(buttons[1]!)
    expect(h.forkAt).not.toHaveBeenCalled()
  })