Monorepo: Gitea CI, docs, auth/sync, backend APIs, gitignore

- Add Gitea Actions workflow; point README to gitea.d-bis.org/Sankofa_Phoenix/SMOA
- Expand .gitignore for Spring H2 data, secrets, Kotlin .kotlin/, tooling
- Track docs/api/generated ReDoc bundle; refresh api docs README
- Android: network/auth/sync, UI shell, tests; backend credentials/integrity APIs
- Docs, scripts (generate-api-docs), modules and core updates

Made-with: Cursor

docs/infrastructure/TURN-SIGNALING.md

@@ -0,0 +1,29 @@
+# TURN and signaling for WebRTC
+
+For meetings and communications beyond STUN-only NAT traversal:
+
+## Coturn (TURN/STUN)
+
+Example `turnserver.conf`:
+
+```conf
+listening-port=3478
+tls-listening-port=5349
+realm=smoa.example.com
+server-name=smoa.example.com
+use-auth-secret
+static-auth-secret=YOUR_LONG_SECRET
+cert=/etc/letsencrypt/live/smoa.example.com/fullchain.pem
+pkey=/etc/letsencrypt/live/smoa.example.com/privkey.pem
+```
+
+Issue **time-limited credentials** (HMAC) from your backend; Android app passes them via `InfrastructureManager.setTurnEndpoints`.
+
+## Signaling
+
+Use **WebSocket** or **HTTPS long-poll** between clients and a small Node/Go/Java service that maps room IDs to SDP/ICE relay. Set `SMOA_SIGNALING_URLS` (comma-separated) in the Android build for `InfrastructureManager`.
+
+## Related
+
+- [nginx-smoa.conf.example](./nginx-smoa.conf.example) – TLS termination  
+- [docker-compose.yml](../../docker-compose.yml) – backend container