Cleanup repo, add Gitea CI/CD workflow, improve error handling

- Remove temp files and reorganize docs
- Add .gitea/workflows/deploy.yml for automated deployment
- Add unreachable host checks to server routes (/:id, logs, start/stop/restart)
- Add unreachable checks to config routes (zomboid, terraria, openttd)
- Return HTTP 503 with unreachable flag instead of crashing

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

docs/todo.md

@@ -0,0 +1,37 @@
+# Homelab TODOs
+
+## Prioritaet Hoch
+
+- [ ] **GSM Modularisierung & Wiederverwendbarkeit**
+  - [ ] Server-Typen als Plugins auslagern (minecraft, factorio, vrising, ...)
+  - [ ] Generisches Interface fuer neue Gameserver-Typen
+  - [ ] Konfiguration per UI statt config.json
+  - [ ] Docker-Compose fuer einfaches Deployment
+  - [ ] Environment-basierte Konfiguration
+  - [ ] Multi-Instanz-Faehigkeit (mehrere Homelabs)
+
+## Prioritaet Mittel
+
+- [ ] Backup-Loesung fuer Gameserver-Welten
+  - [ ] Automatische Snapshots (taeglich)
+  - [ ] Offsite-Backup (Nextcloud/S3)
+  - [ ] Restore-Prozedur dokumentieren
+
+- [ ] Monitoring-Alerts
+  - [ ] Discord Webhook bei Server-Crash
+  - [ ] Email-Benachrichtigung optional
+  - [ ] Alerting-Regeln in Prometheus/Grafana
+
+- [ ] Automatische Restarts bei Crash
+  - [ ] Watchdog-Service implementieren
+  - [ ] Health-Checks definieren
+  - [ ] Restart-Limits (kein Endlos-Loop)
+
+## Prioritaet Niedrig
+
+- [ ] Dark/Light Mode Toggle im Frontend
+- [ ] Server-Logs durchsuchbar machen
+- [ ] Scheduled Restarts (z.B. taeglich 4 Uhr)
+- [ ] Player-Statistiken (Spielzeit, Join-History)
+- [ ] Changelog/Audit-Log fuer Admin-Aktionen
+