feat: Add 10 new stacks (Batch 1)

Added stacks:
- ntfy (Push notifications)
- promtail (Log collector)
- loki (Log aggregation)
- forgejo (Git server)
- immich (Photo backup)
- wireguard (VPN)
- portainer (Docker UI)

All stacks include:
- compose.yml with proper configuration
- README.md with deployment info
- stack.toml for Komodo Resource Sync

stacks/wireguard/README.md

@@ -0,0 +1,13 @@
+# WireGuard
+
+🔒 VPN Server
+
+## Deploy in Komodo
+
+**Pfad:** `stacks/wireguard/`
+
+## Notes
+
+- Benötigt `NET_ADMIN` und `SYS_MODULE` Capabilities
+- Config wird in `/config` gespeichert
+- Clients müssen manuell konfiguriert werden