feat: add workspace file management and embedded browsing

Users previously had to leave the workbar to manage project files and inspect Git branches or commit history. Add file and directory creation, rename, move, delete and properties, plus searchable branches, branch creation and switching, explicit fetch, and commit file diffs.

Keep file previews in the right workspace pane with directory expansion, selection, scroll and focus preserved on return. Add compact action menus, directory pickers, preview refresh and source switching. Embed the shared browser session directly in the workbar with navigation, resizing and fullscreen controls instead of a separate interaction window.

Moves stay within the current workspace, deletion is permanent after confirmation, and Git switch reports conflicts without discarding or stashing changes. Typecheck, lint and staged whitespace checks pass; existing full-suite failures and the blocked real remote directory validation remain recorded in the workbar progress document.

Release note: 可在右侧工作区管理文件、切换 Git 分支并查看提交历史，返回预览后保留浏览位置；浏览器支持在工作栏内直接交互和全屏显示。

src/main/browser/browser-service.test.ts

@@ -14,6 +14,7 @@ type HarnessSlot = {
   currentUrl?: string
   approvedOrigin?: string
   emitLoading(isLoading: boolean): void
+  emitNavigation(url: string): void
   session: BrowserSessionLike
   driver: BrowserDriverLike
 }
@@ -55,6 +56,7 @@ function createHarness(options: {
       getURL: () => slot.currentUrl ?? `${slot.currentOrigin}/page`
     } as BrowserWebContents
     const loadingListeners = new Set<(isLoading: boolean) => void>()
+    const navigationListeners = new Set<(url: string) => void>()
     let isLoading = false
     const session: BrowserSessionLike = {
       webContents,
@@ -67,7 +69,11 @@ function createHarness(options: {
         loadingListeners.add(listener)
         return () => loadingListeners.delete(listener)
       }),
-      openInteraction: vi.fn(async () => undefined),
+      onNavigationChange: vi.fn((listener) => {
+        navigationListeners.add(listener)
+        return () => navigationListeners.delete(listener)
+      }),
+      setViewport: vi.fn(),
       stopLoading: vi.fn(),
       ...(options.captureScreenshot
         ? { captureScreenshot: vi.fn(options.captureScreenshot) }
@@ -123,6 +129,13 @@ function createHarness(options: {
         for (const listener of loadingListeners) {
           listener(loading)
         }
+      },
+      emitNavigation: (url: string) => {
+        slot.currentUrl = url
+        slot.currentOrigin = canonicalizeBrowserUrl(url).origin
+        for (const listener of navigationListeners) {
+          listener(url)
+        }
       }
     })
     slots.push(slot)
@@ -152,6 +165,42 @@ afterEach(() => {
 })
 
 describe('BrowserService', () => {
+  it('presents one session in the shared viewport and tracks user navigation', async () => {
+    const harness = createHarness()
+    const bounds = { x: 900, y: 120, width: 420, height: 640 }
+    const states: BrowserLiveState[] = []
+    harness.service.onState((state) => states.push(state))
+    harness.service.setViewport('conversation', bounds)
+
+    await harness.service.navigate(
+      'conversation',
+      'https://example.com/',
+      new AbortController().signal
+    )
+    const slot = harness.slots[0]
+    expect(slot?.session.setViewport).toHaveBeenCalledWith(bounds)
+
+    vi.mocked(slot!.driver.getNavigationMetadata).mockResolvedValueOnce({
+      url: 'https://example.com/account',
+      canGoBack: true
+    })
+    slot?.emitNavigation('https://example.com/account')
+    await vi.waitFor(() => {
+      expect(states.at(-1)).toMatchObject({
+        status: 'ready',
+        url: 'https://example.com/account',
+        canGoBack: true
+      })
+    })
+    expect(harness.service.getOrigin('conversation')).toBe(
+      'https://example.com'
+    )
+
+    harness.service.setViewport()
+    expect(slot?.session.setViewport).toHaveBeenLastCalledWith(undefined)
+    await harness.service.dispose()
+  })
+
   it('publishes browser status and live frames through session cleanup', async () => {
     const harness = createHarness()
     const states: Array<{
@@ -464,58 +513,6 @@ describe('BrowserService', () => {
     await harness.service.dispose()
   })
 
-  it('pauses agent operations while the user interacts with the same session', async () => {
-    const harness = createHarness()
-    const signal = new AbortController().signal
-    const states: BrowserLiveState[] = []
-    harness.service.onState((state) => states.push(state))
-    await harness.service.navigate(
-      'conversation',
-      'https://a.example/',
-      signal
-    )
-    const interactionGate = deferred<
-      Awaited<ReturnType<BrowserSessionLike['openInteraction']>>
-    >()
-    const slot = harness.slots[0]
-    if (!slot) {
-      throw new Error('slot missing')
-    }
-    vi.mocked(slot.session.openInteraction).mockReturnValueOnce(
-      interactionGate.promise
-    )
-
-    const interaction = harness.service.interact(
-      'conversation',
-      signal
-    )
-    await vi.waitFor(() =>
-      expect(slot.session.openInteraction).toHaveBeenCalledOnce()
-    )
-    const snapshot = harness.service.snapshot('conversation', signal)
-    await new Promise((resolve) => setTimeout(resolve, 10))
-    expect(slot.driver.snapshot).not.toHaveBeenCalled()
-
-    interactionGate.resolve({
-      type: 'image',
-      mimeType: 'image/jpeg',
-      data: 'closing-frame'
-    })
-    await interaction
-    expect(states.slice(-2).map((state) => state.status)).toEqual([
-      'interactive',
-      'ready'
-    ])
-    expect(states.at(-1)?.frameDataUrl).toBe(
-      'data:image/jpeg;base64,closing-frame'
-    )
-    expect(harness.service.getSessionCount()).toBe(1)
-    expect(slot.session.dispose).not.toHaveBeenCalled()
-    await snapshot
-    expect(slot.driver.snapshot).toHaveBeenCalledOnce()
-    await harness.service.dispose()
-  })
-
   it('does not let a canceled queued waiter clear the active operation owner', async () => {
     const harness = createHarness()
     const signal = new AbortController().signal