feat: monorepo structure with Django backend, React frontend, and Expo mobile app

- Backend: Django 5 + DRF with accounts, documents, collections, and reading apps
  - Custom User model with email-based auth, JWT via SimpleJWT
  - Full CRUD viewsets with ModelSerializer + DRF routers
  - pytest, Ruff, drf-spectacular (OpenAPI), whitenoise
  - Dockerfile for production deployment

- Frontend: React 18 + TypeScript + Vite
  - Lazy-loaded routes with ProtectedRoute/PublicRoute guards
  - Auth context with useReducer, token refresh interceptor
  - Pages: Login, Register, Library, Document Detail, Reader, Collections, Settings
  - Dark theme, responsive grid layout, Vite proxy to Django backend

- Mobile: Expo SDK 51 + React Native + Expo Router
  - File-based routing with login, register, and library screens
  - AsyncStorage for token persistence, token refresh interceptor
  - Shared API types via @cloud-reader/shared workspace package

- Shared: TypeScript types (API responses, auth, documents, etc.)
- CI/CD: 3 independent GitHub Actions pipelines (backend, frontend, mobile)

backend/apps/reading/views.py

@@ -0,0 +1,49 @@
+from rest_framework import permissions, viewsets
+
+from .models import Bookmark, Highlight, ReadingProgress
+from .serializers import (
+    BookmarkSerializer,
+    HighlightSerializer,
+    ReadingProgressSerializer,
+    ReadingProgressUpdateSerializer,
+)
+
+
+class BookmarkViewSet(viewsets.ModelViewSet):
+    """User bookmarks for documents."""
+    serializer_class = BookmarkSerializer
+    permission_classes = [permissions.IsAuthenticated]
+
+    def get_queryset(self):
+        return Bookmark.objects.filter(user=self.request.user).select_related("document")
+
+    def perform_create(self, serializer):
+        serializer.save(user=self.request.user)
+
+
+class HighlightViewSet(viewsets.ModelViewSet):
+    """User highlights for documents."""
+    serializer_class = HighlightSerializer
+    permission_classes = [permissions.IsAuthenticated]
+
+    def get_queryset(self):
+        return Highlight.objects.filter(user=self.request.user).select_related("document")
+
+    def perform_create(self, serializer):
+        serializer.save(user=self.request.user)
+
+
+class ReadingProgressViewSet(viewsets.ModelViewSet):
+    """Reading progress tracker."""
+    permission_classes = [permissions.IsAuthenticated]
+
+    def get_serializer_class(self):
+        if self.action in ("create", "update", "partial_update"):
+            return ReadingProgressUpdateSerializer
+        return ReadingProgressSerializer
+
+    def get_queryset(self):
+        return ReadingProgress.objects.filter(user=self.request.user).select_related("document")
+
+    def perform_create(self, serializer):
+        serializer.save(user=self.request.user)