Move out app init

ui/desktop/src/App.test.tsx

@@ -104,6 +104,7 @@ vi.mock('./contexts/ChatContext', () => ({
       recipeConfig: null,
     },
     setChat: vi.fn(),
+    setPairChat: vi.fn(), // Keep this from HEAD
     resetChat: vi.fn(),
     hasActiveSession: false,
     setRecipeConfig: vi.fn(),
@@ -115,6 +116,7 @@ vi.mock('./contexts/ChatContext', () => ({
     clearDraft: vi.fn(),
     contextKey: 'hub',
   }),
+  DEFAULT_CHAT_TITLE: 'New Chat', // Keep this from HEAD
 }));
 
 vi.mock('./contexts/DraftContext', () => ({
@@ -137,19 +139,6 @@ vi.mock('./components/AnnouncementModal', () => ({
   default: () => null,
 }));
 
-vi.mock('./hooks/useChat', () => ({
-  useChat: () => ({
-    chat: {
-      id: 'test-id',
-      title: 'Test Chat',
-      messages: [],
-      messageHistoryIndex: 0,
-      recipeConfig: null,
-    },
-    setChat: vi.fn(),
-  }),
-}));
-
 // Mock react-router-dom to avoid HashRouter issues in tests
 vi.mock('react-router-dom', () => ({
   HashRouter: ({ children }: { children: React.ReactNode }) => <>{children}</>,