feat: optimize IPC initialization and context management for improved app performance

- Deferred IPC-heavy initialization to occur after the first paint to prevent app freezing on Windows.
- Staggered notification listener setup to avoid saturating the UV thread pool during startup.
- Updated context system initialization to be lazy, ensuring local context is always ready without upfront costs.
- Enhanced data fetching sequence to reduce simultaneous IPC calls, improving overall responsiveness.

src/renderer/App.tsx

@@ -23,27 +23,28 @@ export const App = (): React.JSX.Element => {
     }
   }, []);
 
-  // Initialize context system first, then notification listeners.
-  // Staggered to avoid flooding the main process with 6+ simultaneous IPC
-  // calls at startup, which saturates the UV thread pool on Windows.
+  // Defer IPC-heavy initialization to after the first paint.
+  // On Windows, firing 6+ IPC calls simultaneously at startup saturates the
+  // UV thread pool (4 threads by default), causing the app to freeze.
+  // Context system init is skipped here — local context is ready by default,
+  // and SSH context is initialized lazily when SSH connects (see below).
   useEffect(() => {
-    let notificationCleanup: (() => void) | undefined;
-
-    void useStore
-      .getState()
-      .initializeContextSystem()
-      .finally(() => {
-        // Start notification listeners after context system is ready
-        notificationCleanup = initializeNotificationListeners();
-      });
-
-    return () => notificationCleanup?.();
+    let cleanup: (() => void) | undefined;
+    const timer = setTimeout(() => {
+      cleanup = initializeNotificationListeners();
+    }, 100);
+    return () => {
+      clearTimeout(timer);
+      cleanup?.();
+    };
   }, []);
 
-  // Refresh available contexts when SSH connection state changes
+  // Initialize context system lazily when SSH connection state changes.
+  // Local-only users never pay the cost of IndexedDB init + context IPC calls.
   useEffect(() => {
     if (!api.ssh?.onStatus) return;
     const cleanup = api.ssh.onStatus(() => {
+      void useStore.getState().initializeContextSystem();
       void useStore.getState().fetchAvailableContexts();
     });
     return cleanup;

src/renderer/store/index.ts

@@ -73,7 +73,18 @@ export function initializeNotificationListeners(): () => void {
   cleanupFns.push(() => {
     useStore.getState().unsubscribeProvisioningProgress();
   });
-  void useStore.getState().fetchTeams();
+  // Stagger IPC data fetches to avoid saturating the UV thread pool on Windows.
+  // Each fetch triggers file I/O in the main process; firing them all at once
+  // blocks all 4 default UV threads simultaneously, freezing the app.
+  void useStore
+    .getState()
+    .fetchTeams()
+    .finally(() => {
+      void useStore.getState().fetchNotifications();
+      if (api.cliInstaller) {
+        void useStore.getState().fetchCliStatus();
+      }
+    });
   const pendingSessionRefreshTimers = new Map<string, ReturnType<typeof setTimeout>>();
   const pendingProjectRefreshTimers = new Map<string, ReturnType<typeof setTimeout>>();
   let teamRefreshTimer: ReturnType<typeof setTimeout> | null = null;
@@ -168,8 +179,7 @@ export function initializeNotificationListeners(): () => void {
     }
   }
 
-  // Fetch after listeners are attached so startup events do not get overwritten by a stale response.
-  void useStore.getState().fetchNotifications();
+  // fetchNotifications() is called in the staggered init chain above (after fetchTeams).
 
   /**
    * Check if a session is visible in any pane (not just the focused pane's active tab).
@@ -363,10 +373,7 @@ export function initializeNotificationListeners(): () => void {
     }
   }
 
-  // Auto-check CLI status on startup
-  if (api.cliInstaller) {
-    void useStore.getState().fetchCliStatus();
-  }
+  // fetchCliStatus() is called in the staggered init chain above (after fetchTeams).
 
   // Listen for CLI installer progress events from main process
   let cliCompletedRevertTimer: ReturnType<typeof setTimeout> | null = null;

src/renderer/store/slices/contextSlice.ts

@@ -226,11 +226,12 @@ function captureSnapshot(state: AppState, contextId: string): ContextSnapshot {
 // =============================================================================
 
 export const createContextSlice: StateCreator<AppState, [], [], ContextSlice> = (set, get) => ({
-  // Initial state
+  // Initial state — local context is always ready, no initialization needed.
+  // initializeContextSystem() is called lazily when SSH connects.
   activeContextId: 'local',
   isContextSwitching: false,
   targetContextId: null,
-  contextSnapshotsReady: false,
+  contextSnapshotsReady: true,
   availableContexts: [{ id: 'local', type: 'local' as const }],
 
   // Initialize context system (called once on app mount)