feat: bookmarks and notes management

- Backend: Django REST Framework API with Bookmark and Note models
  - ViewSets with user-scoped querysets and select_related for N+1 prevention
  - Create/List/Detail/Update/Delete endpoints
  - Batch delete operations
  - Unique constraint on user+book+page for bookmarks
  - IsOwner permission class for object-level access control
  - Full serializer validation (page > 0, non-empty content, duplicate check)
  - 30+ pytest-django tests covering CRUD, auth, filtering, edge cases

- Frontend: React TypeScript components
  - AnnotationsContext with useReducer for state management
  - BookmarkList, NoteList, AddAnnotationForm, AnnotationsDashboard
  - Inline note editing with immediate save
  - Batch delete support
  - API client with JWT auto-refresh interceptors
  - Paginated query hook for infinite scroll support
  - Responsive CSS with loading/empty states

- Infrastructure: Django project with custom User model, JWT auth, CORS
  - PostgreSQL database models with proper FK and indexes
  - Django admin configuration for all models

docker-compose.yml

@@ -0,0 +1,52 @@
+services:
+  db:
+    image: postgres:15
+    restart: unless-stopped
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+    environment:
+      POSTGRES_DB: cloudreader
+      POSTGRES_USER: cloudreader
+      POSTGRES_PASSWORD: cloudreader
+    ports:
+      - "5432:5432"
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U cloudreader -d cloudreader"]
+      interval: 5s
+      timeout: 5s
+      retries: 10
+
+  api:
+    build:
+      context: ./api
+    ports:
+      - "8000:8000"
+    environment:
+      DATABASE_URL: "postgres://cloudreader:cloudreader@db:5432/cloudreader"
+      DJANGO_SECRET_KEY: "dev-secret-key-change-in-production"
+      DJANGO_DEBUG: "True"
+    volumes:
+      - ./api:/app
+      - book_uploads:/app/media
+    command: >
+      sh -c "python manage.py migrate && python manage.py runserver 0.0.0.0:8000"
+    depends_on:
+      db:
+        condition: service_healthy
+
+  web:
+    build:
+      context: ./web
+    ports:
+      - "3000:3000"
+    environment:
+      VITE_API_URL: "http://localhost:8000"
+    volumes:
+      - ./web:/app
+      - /app/node_modules
+    depends_on:
+      - api
+
+volumes:
+  postgres_data:
+  book_uploads: