Complete Phase 2: Card import, deck building, and full API

- Add card import feature with fuzzy matching
- Implement deck CRUD and management endpoints
- Add user data APIs for groups, networks, preferences, activity, replays
- Create comprehensive API documentation (API_DOCUMENTATION.md)
- Add ENDPOINT_AUDIT.md for endpoint verification
- Update documentation (README, ROADMAP, state.json)
- Update architecture blueprint and Cockatrice analysis
- All Phase 2 deliverables complete and documented

backend/requirements.txt

@@ -34,3 +34,10 @@ aiosqlite==0.20.0
 
 # Linting
 ruff==0.6.5
+
+# Card import and fuzzy matching
+python-Levenshtein==0.25.1
+thefuzz==0.22.1
+openpyxl==3.1.2
+pandas==2.2.2
+odfpy==1.4.1