feat(timetable): add page components, services, stores and types

- Add timetable page components:
  - ClassesListPage.tsx (browse and search classes)
  - MyClassesPage.tsx (student enrolled classes)
  - EnrollmentRequestsPage.tsx (teacher approval interface)
  - TimetablePage.tsx (weekly schedule view)
  - LessonViewPage.tsx (TLDraw-integrated lesson view)
- Add timetableService.ts for API communication
- Add timetableStore.ts for state management
- Add timetable.types.ts for TypeScript definitions
- Add common components (LoadingSpinner, ErrorMessage, EmptyState)
- Add .env.development with local development configuration

.env.development

@@ -0,0 +1,40 @@
+VITE_SUPABASE_ANON_KEY=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJhdWQiOiJhdXRoZW50aWNhdGVkIiwiaWF0IjoxNzcxODE3MjE5LCJpc3MiOiJzdXBhYmFzZSIsInN1YiI6IjAwMDAwMDAwLTAwMDAtMDAwMC0wMDAwLTAwMDAwMDAwMDAwMCIsImV4cCI6MzM0ODYxNzIxOSwicm9sZSI6ImFub24ifQ.JbmQOTOBAzpBJ9JttOrGlo_JTXDXhCjYMjKiFvRkaNQ
+PORT_FRONTEND=5173
+PORT_FRONTEND_HMR=3002
+PORT_API=8000
+PORT_SUPABASE=8000
+
+HOST_FRONTEND=192.168.0.94:5173
+VITE_PORT_FRONTEND=5173
+VITE_PORT_FRONTEND_HMR=5173
+
+VITE_APP_NAME="Classroom Copilot"
+VITE_SUPER_ADMIN_EMAIL=[email protected]
+VITE_DEV=true
+VITE_FRONTEND_SITE_URL=http://192.168.0.94:5173
+VITE_APP_HMR_URL=http://192.168.0.94:5173
+
+# Supabase is on external container - use its IP
+VITE_SUPABASE_URL=http://192.168.0.155:8000
+
+# API should use localhost for local development
+VITE_API_URL=http://192.168.0.94:8000
+VITE_API_BASE=http://192.168.0.94:8000
+
+# Neo4j
+VITE_NEO4J_URL=bolt://192.168.0.208:7687
+VITE_NEO4J_USER=neo4j
+VITE_NEO4J_PASSWORD=kevlarai
+
+# LLM
+VITE_LLM_PROVIDER=ollama
+VITE_OLLAMA_API_URL=https://ollama.kevlarai.com
+
+# Microsoft
+VITE_MICROSOFT_CLIENT_ID=dummy_client_id
+VITE_MICROSOFT_CLIENT_SECRET_DESC="Microsoft OAuth client secret"
+VITE_MICROSOFT_CLIENT_SECRET_ID=dummy_secret_id
+VITE_MICROSOFT_CLIENT_SECRET=dummy_secret
+VITE_MICROSOFT_TENANT_ID=common
+
+VITE_SEARCH_URL=http://localhost:8888