feat: uv config other feats

- add uv configuration for the backend
- update frontend to make auth work
- add new auth endpoints
- add bookmars feat
- add reader feat

backend/.env.example

@@ -5,4 +5,12 @@ DB_NAME=cloud_reader
 DB_USER=postgres
 DB_PASSWORD=postgres
 DB_HOST=localhost
-DB_PORT=5432
+DB_PORT=5432
+
+# Open Library metadata enrichment (optional)
+OPENLIBRARY_ENABLED=true
+OPENLIBRARY_PREFERRED_LANG=es
+OPENLIBRARY_FALLBACK_LANG=en
+OPENLIBRARY_TIMEOUT_SECONDS=10
+OPENLIBRARY_CONNECT_TIMEOUT_SECONDS=15
+OPENLIBRARY_USER_AGENT=CloudReader/1.0