🏓 Initial ServeSync demo build

- FastAPI backend with PostgreSQL + Redis
- 4 core features: Registration, Courts, Matchmaking, Tournament
- Double elimination tournament with bracket visualization
- ELO-based matchmaking (Stage 1 Open, Stage 2 Skill-Based)
- Real-time WebSocket updates
- TV Screen display for courts
- Vue 3 + Tailwind CSS frontend
- Seed data: 12 players, 4 courts, active matches, tournament in progress
- Docker compose stack with Nginx reverse proxy

backend/app/models/__init__.py

@@ -0,0 +1,5 @@
+from app.models.player import Player
+from app.models.court import Court
+from app.models.booking import Booking
+from app.models.match import Match, MatchPlayer
+from app.models.tournament import Tournament, TournamentEntry, TournamentMatch