implement frontend skeleton with tab navigation and service layer

- Add tab-based navigation (Chat, Calendar) using Expo-Router
- Create auth screens (login, register) as skeletons
- Add dynamic routes for event detail and note editing
- Implement service layer (ApiClient, AuthService, EventService, ChatService)
- Add Zustand stores (AuthStore, EventsStore) for state management
- Create EventCard and EventConfirmDialog components
- Update CLAUDE.md with new frontend architecture documentation
- Add Zustand and FlashList to technology stack

apps/client/tsconfig.json

@@ -2,12 +2,14 @@
   "extends": "../../tsconfig.json",
   "compilerOptions": {
     "target": "ES2020",
-    "module": "CommonJS",
+    "module": "ESNext",
     "outDir": "dist",
     "strict": true,
     "esModuleInterop": true,
     "forceConsistentCasingInFileNames": true,
-    "skipLibCheck": true
+    "skipLibCheck": true,
+    "jsx": "react-native",
+    "moduleResolution": "bundler"
   },
   "include": [
     "**/*.ts",