Refactor settings system and improve context initialization

Backend:
- Add type validation and coercion for settings API
- Implement SettingStorage and SettingType in registry
- Improve CRUD operations for settings

Frontend:
- Refactor Theme, Language, Sidebar, ViewMode contexts
- Simplify admin components (GeneralTab, SettingsTab, UsersTab)
- Add new settings endpoints to API client
- Improve App initialization flow

Infrastructure:
- Update Dockerfile and docker-compose.yml
- Add .dockerignore
- Update Makefile and README

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/api/v1/health.py

@@ -12,7 +12,7 @@ router = APIRouter()
 
 
 @router.get("")
-async def health_check(db: Session = Depends(get_db)):
+def health_check(db: Session = Depends(get_db)):
     """
     Health check endpoint that verifies database connectivity.