fix(changes): 会话事件改走宿主 changes.ops 路由 + diff 展开二级设置 + 视觉迭代

CI 修复（plugin-mount 的 ctx.sessions.get TypeError ×1003）：
- 客户端 runtime 无事件日志面——badge/SessionLens 原在客户端直读
  ctx.sessions.get(id).events / ctx.on('session/event')，全部不可达。
- 新增宿主路由 changes.ops：live 会话日志优先，冷会话回放
  sessionPersistence.inspect；afterSeq 增量（缺省游标含 seq 0，
  显式游标为 seq > afterSeq，同 sidechat.events 约定），窗口上限
  4000 与客户端累加器一致。
- ChangesTab 轮询（mount 一拉 + visible 2.5s 增量）折入 ops，写
  模块级 opCounts 缓存供 badge 同步读取；SessionLens 改纯展示。

diff 展开二级设置（changesDiffFloat，默认浮窗）：
- prefs 四处接线 + git tab settings select（浮窗/面板，图标选项卡）
- 预览面板「展开为 diff tab」按设置落点：浮窗居中弹出或源 pane
  下方 split；i18n 全 21 词典同步。

视觉迭代（真机挂载截图审查后调整）：
- Session 视角：kind 徽章为左轨，大小+相对时间右对齐元列；失败
  操作行红色内嵌条；文件组头降为三级标签并加组间距。
- Git 视角：untracked '?' 徽章与新增同绿色；stage 按钮改 plus 图标。
- diff 折叠行：可展开折叠带 › 箭头 + 次级对比度，静态 gap 不再
  显示 pointer/hover；预览头路径改尾部截断（RTL 技巧，保文件名）。

验证：typecheck ✓ / vitest 1123 ✓ / pnpm test:mount（钉 alpha.2 CLI）
14/14 ✓；真机挂载截图（badge=5、双视角、浮窗展开）0 console error。

src/client/changes/ChangesTab.tsx

@@ -3,23 +3,45 @@
  * (repository truth: staged/unstaged files, commit box, history) and the
  * session round (agent truth: every file the model read, wrote, or edited).
  * Both lenses preview their selections in a shared resizable bottom pane
- * ({@link DiffPane}); git targets can expand into the dedicated diff tab.
+ * ({@link DiffPane}); git targets expand into the dedicated diff tab —
+ * docked in a pane, or floated as a free window per the tab's setting.
  * The active lens and the pane height persist in the tab's meta, so the tab
  * reopens exactly where it was left.
+ *
+ * The session events ride the host's `changes.ops` route (the client
+ * runtime exposes no event-log face): the tab pulls the delta past its
+ * cursor while visible, folds it into ops, and publishes the op count to a
+ * module-level cache the tab-strip badge reads.
  */
-import { useState } from 'react'
+import { useCallback, useEffect, useRef, useState } from 'react'
+import type { SidebarSessionEvent } from '../../context-types.ts'
 import type { TabComponentProps } from '../service.ts'
 import { t } from '../locales.ts'
-import type { SidebarDiffRef } from '../state.ts'
+import { api } from '../api.ts'
+import { floatTab, type SidebarDiffRef } from '../state.ts'
 import { GitLens } from './GitLens.tsx'
 import { SessionLens } from './SessionLens.tsx'
 import { DiffPane, diffTabOf, type ChangesPreview } from './DiffPane.tsx'
-import type { FileOp } from './ops.ts'
+import { extractFileOps, knownContentBefore, type FileOp } from './ops.ts'
 import css from './changes.module.css'
 
 /** The default preview pane height (px) before the first drag. */
 const PANE_HEIGHT_DEFAULT = 300
 
+/** Cap on accumulated events: the lens shows the recent window, not eternity
+ *  (the host enforces the same bound per response). */
+const EVENTS_CAP = 4000
+
+/** Live op count per session: the tab's poller writes, the badge reads (a
+ *  badge cannot fetch — it must resolve synchronously during render). */
+const opCounts = new Map<string, number>()
+
+/** The session's traced-op count as of the last poll (undefined before the
+ *  tab has ever pulled; 0 hides the badge pill). */
+export function opCountOf(sessionId: string): number | undefined {
+  return opCounts.get(sessionId)
+}
+
 type Lens = 'git' | 'session'
 
 /** The persisted tab meta (JSON-serializable; rides the layout). */
@@ -36,6 +58,50 @@ export function ChangesTab({ ctx, store, scope, tab, visible, onOpenFile, onOpen
     typeof meta.previewH === 'number' && meta.previewH >= 140 ? meta.previewH : PANE_HEIGHT_DEFAULT,
   )
 
+  // ── Session-event accumulation: one pull on mount, then a 2.5s delta
+  //    poll while visible (paused otherwise; the next visible tick catches
+  //    up). The cursor is the last delivered seq, so each poll ships only
+  //    what the accumulator lacks. ────────────────────────────────────────
+  const eventsRef = useRef<readonly SidebarSessionEvent[]>([])
+  const seqRef = useRef(0)
+  const pollGen = useRef(0)
+  const [opsError, setOpsError] = useState(false)
+  const [tick, setTick] = useState(0)
+  const pull = useCallback(async (): Promise<void> => {
+    const generation = pollGen.current
+    try {
+      const { events, lastSeq } = await api.changesOps(scope, seqRef.current)
+      if (generation !== pollGen.current) return
+      if (events.length > 0) {
+        const merged = [...eventsRef.current, ...events]
+        eventsRef.current = merged.length > EVENTS_CAP ? merged.slice(merged.length - EVENTS_CAP) : merged
+      }
+      if (lastSeq > seqRef.current) seqRef.current = lastSeq
+      opCounts.set(scope.sessionId, extractFileOps(eventsRef.current).length)
+      setOpsError(false)
+      setTick(value => value + 1)
+    } catch {
+      // Offline / route unavailable: keep the last fold; surface it inline
+      // only while nothing has ever loaded.
+      if (generation === pollGen.current) setOpsError(true)
+    }
+  }, [scope.sessionId, scope.cwd])
+  useEffect(() => {
+    pollGen.current += 1
+    eventsRef.current = []
+    seqRef.current = 0
+    setOpsError(false)
+  }, [scope.sessionId])
+  useEffect(() => {
+    void pull()
+    if (!visible) return
+    const timer = window.setInterval(() => { void pull() }, 2_500)
+    return () => { window.clearInterval(timer) }
+  }, [visible, pull])
+  // tick only forces the re-render; the fold reads the ref directly.
+  void tick
+  const ops = extractFileOps(eventsRef.current)
+
   /** Persist a meta patch onto the tab (lens choice, pane height). */
   const patchMeta = (patch: ChangesMeta): void => {
     ctx.get('betterSidebar')?.updateTab(tab.id, {
@@ -55,8 +121,22 @@ export function ChangesTab({ ctx, store, scope, tab, visible, onOpenFile, onOpen
   }
 
   /** Preview one session op (with its best-effort prior content snapshot). */
-  const previewOp = (path: string, op: FileOp, prior: string | undefined): void => {
-    setPreview({ kind: 'op', path, op, prior })
+  const previewOp = (path: string, op: FileOp): void => {
+    setPreview({ kind: 'op', path, op, prior: knownContentBefore(ops, path, op) })
+  }
+
+  /** Expand the current git preview into the dedicated diff tab: docked
+   *  into the shell's diff pane, or floated as a free window centered on
+   *  the viewport when the tab's diff-open setting asks for it (default). */
+  const expandPreview = (): void => {
+    if (preview?.kind !== 'git') return
+    const diffTab = diffTabOf(preview.ref)
+    onOpenDiff?.(diffTab)
+    if (store.getPrefs().changesDiffFloat !== false) {
+      const x = Math.round(window.innerWidth / 2)
+      const y = Math.round(window.innerHeight / 2)
+      store.reduce(state => floatTab(state, diffTab.id, x, y))
+    }
   }
 
   const previewKey = (target: ChangesPreview): string => target.kind === 'git'
@@ -102,9 +182,8 @@ export function ChangesTab({ ctx, store, scope, tab, visible, onOpenFile, onOpen
         )
         : (
           <SessionLens
-            ctx={ctx}
-            scope={scope}
-            visible={visible}
+            ops={ops}
+            loadError={opsError && ops.length === 0}
             onPreview={previewOp}
             selectedCallId={preview !== null && preview.kind === 'op' ? preview.op.callId : null}
           />
@@ -117,9 +196,7 @@ export function ChangesTab({ ctx, store, scope, tab, visible, onOpenFile, onOpen
           height={paneHeight}
           onHeightCommit={(height) => { setPaneHeight(height); patchMeta({ previewH: height }) }}
           onClose={() => { setPreview(null) }}
-          onExpand={() => {
-            if (preview.kind === 'git') onOpenDiff?.(diffTabOf(preview.ref))
-          }}
+          onExpand={expandPreview}
         />
       )}
     </div>

src/client/changes/GitLens.tsx

@@ -12,8 +12,8 @@
  */
 import { useCallback, useEffect, useRef, useState, type MouseEvent, type ReactNode } from 'react'
 import {
-  Button, IconBranchOutline16, IconCodeOutline16, IconCopyOutline16, IconRefreshOutline16,
-  IconTrashOutline16, Input, Menu, Modal, writeClipboard,
+  Button, IconCodeOutline16, IconCopyOutline16, IconPlusOutline16,
+  IconRefreshOutline16, IconTrashOutline16, Input, Menu, Modal, writeClipboard,
 } from '@deepseek-ai/dsh-client-ui-primitives'
 import type { GitLogEntry, GitStatusEntry, GitStatusResult, GitWorktree, SessionScope } from '../api.ts'
 import { api } from '../api.ts'
@@ -418,7 +418,7 @@ export function GitLens(props: GitLensProps) {
           disabled={busy}
           onClick={() => { void stageEntry(entry, staged) }}
         >
-          {staged ? <IconTrashOutline16 /> : <IconBranchOutline16 />}
+          {staged ? <IconTrashOutline16 /> : <IconPlusOutline16 />}
         </button>
       </div>
     )
@@ -596,7 +596,7 @@ export function GitLens(props: GitLensProps) {
                 : []),
               fileMenu?.staged === true
                 ? { id: 'stage', label: t('unstage'), icon: <IconTrashOutline16 size={14} /> }
-                : { id: 'stage', label: t('stage'), icon: <IconBranchOutline16 size={14} /> },
+                : { id: 'stage', label: t('stage'), icon: <IconPlusOutline16 size={14} /> },
               ...(fileMenu !== null && !isUntracked(fileMenu.entry)
                 ? [{ id: 'discard', label: t('discard'), icon: <IconTrashOutline16 size={14} />, danger: true }]
                 : []),

src/client/changes/SessionLens.tsx

@@ -1,62 +1,34 @@
 /**
  * The session lens of the changes tab: agent truth — every file the model
- * read, wrote, or edited in this session (folded from the session event
- * log), grouped by file, newest first, with kind filters. Clicking an op
- * previews it in the tab's shared bottom pane (see {@link DiffPane}): writes
- * and edits as line diffs, reads as a line-numbered content view, failures
- * as their real error text. Live `tool/call` / `tool/result` events append
- * while the tab is visible (bounded; paused and caught up when hidden).
+ * read, wrote, or edited in this session, grouped by file, newest first,
+ * with kind filters. Clicking an op previews it in the tab's shared bottom
+ * pane (see {@link DiffPane}): writes and edits as line diffs, reads as a
+ * line-numbered content view, failures as their real error text. The ops
+ * arrive pre-folded from the tab (which owns the event poll); this
+ * component is purely presentational.
  */
-import { useEffect, useMemo, useRef, useState, type ReactNode } from 'react'
-import type { SidebarSessionEvent } from '../../context-types.ts'
-import type { Context } from '../../context-types.ts'
-import type { SessionScope } from '../api.ts'
+import { useMemo, useState, type ReactNode } from 'react'
 import { relativeTime, t } from '../locales.ts'
-import { extractFileOps, groupByFile, knownContentBefore, type FileOp, type FileOpKind } from './ops.ts'
+import { groupByFile, type FileOp, type FileOpKind } from './ops.ts'
 import { formatBytes } from '../diff/rows.ts'
 import css from './changes.module.css'
 
-/** Cap on accumulated events: the lens shows the recent window, not eternity. */
-const EVENTS_CAP = 4000
-
 /** The op-kind filter chips: 'all' or one concrete kind. */
 type OpFilter = 'all' | FileOpKind
 
 export interface SessionLensProps {
-  ctx: Context
-  scope: SessionScope
-  /** Preview one op in the shared bottom pane (with its best-effort prior content). */
-  onPreview: (path: string, op: FileOp, prior: string | undefined) => void
+  /** The folded file operations, newest first (the tab's poll owns them). */
+  ops: readonly FileOp[]
+  /** Every poll failed and nothing loaded: an inline notice, not an empty
+   *  state that would read as "no operations". */
+  loadError: boolean
+  /** Preview one op in the shared bottom pane. */
+  onPreview: (path: string, op: FileOp) => void
   /** The op currently previewed (row highlight); null when the pane is closed. */
   selectedCallId: string | null
-  /** Fold events only while the tab is actually visible. */
-  visible: boolean
 }
 
-export function SessionLens({ ctx, scope, onPreview, selectedCallId, visible }: SessionLensProps) {
-  // The event log snapshot seeds the lens once; live tool/call and
-  // tool/result events append (bounded) and re-extract while visible.
-  const eventsRef = useRef<readonly SidebarSessionEvent[] | null>(null)
-  if (eventsRef.current === null) {
-    eventsRef.current = ctx.sessions.get(scope.sessionId)?.events ?? []
-  }
-  const [tick, setTick] = useState(0)
-  useEffect(() => {
-    if (typeof ctx.on !== 'function') return
-    const off = ctx.on('session/event', (session: unknown, event: SidebarSessionEvent) => {
-      const sessionId = (session as { id?: unknown } | null)?.id
-      if (sessionId !== scope.sessionId) return
-      if (event.type !== 'tool/call' && event.type !== 'tool/result') return
-      const list = [...eventsRef.current ?? [], event]
-      eventsRef.current = list.length > EVENTS_CAP ? list.slice(list.length - EVENTS_CAP) : list
-      if (visible) setTick(value => value + 1)
-    })
-    return () => { off() }
-  }, [ctx, scope.sessionId, visible])
-  // Becoming visible again catches up on events appended while paused.
-  useEffect(() => { if (visible) setTick(value => value + 1) }, [visible])
-
-  const ops = useMemo(() => extractFileOps(eventsRef.current ?? []), [tick])
+export function SessionLens({ ops, loadError, onPreview, selectedCallId }: SessionLensProps) {
   const [filter, setFilter] = useState<OpFilter>('all')
   const filteredOps = useMemo(
     () => (filter === 'all' ? ops : ops.filter(op => op.kind === filter)),
@@ -91,7 +63,8 @@ export function SessionLens({ ctx, scope, onPreview, selectedCallId, visible }:
         {chip('read', t('changesRead'), counts.get('read') ?? 0)}
       </div>
       <div className={css.sessionList}>
-        {ops.length === 0 && <div className={css.empty}>{t('changesSessionEmpty')}</div>}
+        {loadError && <div className={css.loadError}>{t('changesLoadError')}</div>}
+        {ops.length === 0 && !loadError && <div className={css.empty}>{t('changesSessionEmpty')}</div>}
         {ops.length > 0 && filteredOps.length === 0 && <div className={css.empty}>{t('changesFilterEmpty')}</div>}
         {[...groups.entries()].map(([path, fileOps]) => (
           <div key={path} className={css.fileGroup}>
@@ -104,19 +77,21 @@ export function SessionLens({ ctx, scope, onPreview, selectedCallId, visible }:
                 data-op-kind={op.kind}
                 data-op-error={op.isError ? 'true' : undefined}
                 data-selected={selectedCallId === op.callId ? 'true' : undefined}
-                onClick={() => { onPreview(path, op, knownContentBefore(ops, path, op)) }}
+                onClick={() => { onPreview(path, op) }}
               >
                 <span className={css.opKind} data-kind={op.kind}>
                   {t(op.kind === 'read' ? 'changesRead' : op.kind === 'write' ? 'changesWrite' : 'changesEdit')}
                 </span>
-                <span className={css.opTime}>{relativeTime(new Date(op.time).toISOString())}</span>
                 {op.running && <span className={css.opFlag}>{t('changesRunning')}</span>}
                 {op.isError && <span className={css.opFlagError}>{t('changesError')}</span>}
-                {op.kind !== 'read' && !op.isError && (
-                  <span className={css.opSize}>
-                    {formatBytes(new Blob([op.edit?.newString ?? op.content ?? '']).size)}
-                  </span>
-                )}
+                <span className={css.opMeta}>
+                  {op.kind !== 'read' && !op.isError && (
+                    <span className={css.opSize}>
+                      {formatBytes(new Blob([op.edit?.newString ?? op.content ?? '']).size)}
+                    </span>
+                  )}
+                  <span className={css.opTime}>{relativeTime(new Date(op.time).toISOString())}</span>
+                </span>
               </button>
             ))}
           </div>

src/client/changes/changes.module.css

@@ -140,8 +140,9 @@
   color: var(--dsw-alias-label-secondary);
 }
 
-/* Status-letter tint: A added / D deleted / M·R modified / C·U conflicts. */
-.gitBadge[data-letter='A'] { color: var(--dsw-alias-state-success-primary); }
+/* Status-letter tint: A added / D deleted / M·R modified / C·U conflicts;
+   untracked '?' reads as a not-yet-added file, so it shares the added tint. */
+.gitBadge[data-letter='A'], .gitBadge[data-letter='?'] { color: var(--dsw-alias-state-success-primary); }
 .gitBadge[data-letter='D'] { color: var(--dsw-alias-state-error-primary); }
 .gitBadge[data-letter='M'], .gitBadge[data-letter='R'] { color: var(--dsw-alias-state-business-primary); }
 .gitBadge[data-letter='C'], .gitBadge[data-letter='U'] { color: var(--dsw-alias-state-warn-primary); }
@@ -316,19 +317,28 @@
 
 .sessionList { flex: 1; min-height: 0; overflow-y: auto; padding: 0 6px 10px; }
 .empty { color: var(--dsw-alias-label-tertiary); padding: 24px 8px; text-align: center; }
+.loadError { margin: 4px 8px; padding: 6px 10px; border-left: 3px solid var(--dsw-alias-state-warn-primary); border-radius: 0 6px 6px 0; color: var(--dsw-alias-label-secondary); font-size: 11px; }
 
-.fileGroup { margin-bottom: 8px; }
-.filePath { display: block; color: var(--dsw-alias-label-secondary); font-family: var(--ds-font-family-code, monospace); font-size: 11px; padding: 2px 4px; word-break: break-all; }
+.fileGroup { margin-bottom: 6px; }
+/* The group label sits between op blocks: extra head padding separates it from
+   the previous file's rows, the first group starts flush. */
+.filePath { display: block; color: var(--dsw-alias-label-tertiary); font-family: var(--ds-font-family-code, monospace); font-size: 11px; padding: 6px 4px 2px; word-break: break-all; }
+.fileGroup:first-child .filePath { padding-top: 2px; }
 .opRow { display: flex; align-items: center; gap: 6px; width: 100%; border: 0; border-radius: 6px; background: transparent; color: var(--dsw-alias-label-primary); font: inherit; font-size: 11px; padding: 3px 5px; cursor: pointer; text-align: left; }
 .opRow:hover { background: var(--dsw-alias-interactive-bg-hover); }
 .opRow[data-selected='true'] { background: var(--dsw-alias-interactive-bg-active); }
+/* A failed op carries a quiet error inset bar (the flag chip names it). */
+.opRow[data-op-error='true'] { box-shadow: inset 2px 0 0 var(--dsw-alias-state-error-primary); }
 .opKind { border-radius: 4px; font-size: 10px; line-height: 16px; padding: 0 5px; background: var(--dsw-alias-interactive-bg-hover); color: var(--dsw-alias-label-secondary); flex: none; }
 .opKind[data-kind='write'] { color: var(--dsw-alias-state-success-primary); }
 .opKind[data-kind='edit'] { color: var(--dsw-alias-state-business-primary); }
+/* Size + relative time ride as one right-aligned cluster so the kind chips
+   form a scannable left rail and the meta column stays flush right. */
+.opMeta { margin-left: auto; display: inline-flex; align-items: baseline; gap: 8px; flex: none; min-width: 0; }
 .opTime { color: var(--dsw-alias-label-tertiary); font-size: 10px; flex: none; }
 .opFlag { color: var(--dsw-alias-state-business-primary); font-size: 10px; flex: none; }
 .opFlagError { color: var(--dsw-alias-state-error-primary); font-size: 10px; flex: none; }
-.opSize { margin-left: auto; color: var(--dsw-alias-label-tertiary); font-size: 10px; flex: none; }
+.opSize { color: var(--dsw-alias-label-tertiary); font-size: 10px; flex: none; font-family: var(--ds-font-family-code, monospace); }
 
 /* ── Shared preview pane ───────────────────────────────────────────────── */
 
@@ -341,7 +351,10 @@
 .diffKind[data-kind='git'] { color: var(--dsw-alias-brand-primary); }
 .diffKind[data-kind='write'] { color: var(--dsw-alias-state-success-primary); }
 .diffKind[data-kind='edit'] { color: var(--dsw-alias-state-business-primary); }
-.diffPath { flex: 1; font-family: var(--ds-font-family-code, monospace); font-size: 11px; word-break: break-all; color: var(--dsw-alias-label-primary); min-width: 0; }
+/* The path keeps its tail (the file name is the identity; directories are
+   context): an RTL paragraph renders an ASCII path in reading order while
+   clipping its HEAD under the ellipsis. */
+.diffPath { flex: 1; direction: rtl; font-family: var(--ds-font-family-code, monospace); font-size: 11px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; color: var(--dsw-alias-label-primary); min-width: 0; }
 .diffStats { flex: none; display: inline-flex; gap: 5px; font-size: 10px; font-family: var(--ds-font-family-code, monospace); }
 
 .iconButton {