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/server/src/services/inference.ts

@@ -493,6 +493,9 @@ async function handleAbortOrError(
     RETURNING project_id, name, updated_at
   `;
   ctx.publishUser({ type: 'session_updated', session_id: sessionId, project_id: failSessRow!.project_id, name: failSessRow!.name, updated_at: failSessRow!.updated_at });
+  // v1.8 mobile-tabs: cancellation is a user-initiated stop, treat as idle;
+  // genuine errors flip the dot red.
+  ctx.publishUser({ type: 'chat_status', chat_id: chatId, status: isAbort ? 'idle' : 'error', at: new Date().toISOString() });
   if (isAbort) {
     ctx.publish(sessionId, {
       type: 'message_complete',
@@ -638,6 +641,7 @@ async function finalizeCompletion(
     RETURNING project_id, name, updated_at
   `;
   ctx.publishUser({ type: 'session_updated', session_id: sessionId, project_id: completeSessRow!.project_id, name: completeSessRow!.name, updated_at: completeSessRow!.updated_at });
+  ctx.publishUser({ type: 'chat_status', chat_id: chatId, status: 'idle', at: new Date().toISOString() });
   ctx.publish(sessionId, {
     type: 'message_complete',
     message_id: assistantMessageId,
@@ -683,6 +687,7 @@ async function runAssistantTurn(
       chat_id: chatId,
       error: 'tool loop depth exceeded',
     });
+    ctx.publishUser({ type: 'chat_status', chat_id: chatId, status: 'error', at: new Date().toISOString() });
     return;
   }
 
@@ -820,6 +825,9 @@ export function createInferenceRunner(
         ...ctx,
         publishUser: (frame) => publishUserFn(user, frame),
       };
+      // v1.8 mobile-tabs: announce working before the async loop starts so
+      // every device subscribed to the user channel sees the amber dot.
+      callCtx.publishUser({ type: 'chat_status', chat_id: chatId, status: 'working', at: new Date().toISOString() });
       const controller = new AbortController();
       let resolveCompleted!: () => void;
       const completed = new Promise<void>((res) => { resolveCompleted = res; });