- Replace Firebase Auth with JWT stored in SharedPreferences - Replace Firestore with REST API calls via new ApiService - Replace Firebase Storage with POST /storage/upload - Remove firebase_auth, firebase_core, cloud_firestore, firebase_storage, firebase_messaging, google_sign_in deps - Add api_service.dart as central HTTP client Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>