feat(mobile): v1.8 tab switcher + branch indicator + git_status tool

Mobile header is now two rows. Row 1: hamburger | project · branch
indicator (live via GET /api/projects/:id/git, 30s poll) | ModelPicker |
FolderTree. Row 2: pane-switcher pill (hand-rolled BottomSheet) +
NewPaneMenu. Chat-within-pane navigation hidden on mobile; users switch
panes via the sheet. Cross-tab status sync via chat_status frames
published from inference.ts at working/idle/error transitions; StatusDot
component renders amber-pulse/green/red/gray on each pane row and on
desktop ChatTabBar tabs. Level 1 git awareness exposes a read-only
git_status tool to the model, backed by services/git_meta.ts (execFile
+ 2s timeout + 30s cache). Workspace.tsx now receives panes/chats hooks
as props (hoisted into Session.tsx) so the header pill shares state
with the pane grid.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/web/src/hooks/sessionEvents.ts

@@ -115,6 +115,16 @@ export interface ProjectUpdatedEvent {
   name: string;
 }
 
+// v1.8 mobile-tabs: broadcast on user channel from inference.ts so any device
+// subscribed sees a chat working/idle/error. Frontend stores per-chat; panes
+// derive their dot from pane.activeChatId.
+export interface ChatStatusEvent {
+  type: 'chat_status';
+  chat_id: string;
+  status: 'working' | 'idle' | 'error';
+  at: string;
+}
+
 export type SessionEvent =
   | SessionRenamedEvent
   | ProjectCreatedEvent
@@ -134,7 +144,8 @@ export type SessionEvent =
   | ChatDeletedEvent
   | ProjectArchivedEvent
   | ProjectUnarchivedEvent
-  | ProjectUpdatedEvent;
+  | ProjectUpdatedEvent
+  | ChatStatusEvent;
 type Listener = (event: SessionEvent) => void;
 
 const listeners = new Set<Listener>();