Fix: Sécurisation CrateDB-Stellio + healthchecks MongoDB/Mosquitto

- Suppression exposition publique ports CrateDB-Stellio (sécurité)
- Ajout service iot-mongodb avec healthcheck fonctionnel (mongo ping)
- Correction healthcheck Mosquitto (port check au lieu de topic)
- Nettoyage container digital-twin-grafana en conflit

docker-compose.mosquitto.yml

@@ -18,7 +18,7 @@ services:
       - mosquitto-logs:/mosquitto/log
     command: mosquitto -c /mosquitto/config/mosquitto.conf
     healthcheck:
-      test: ["CMD", "mosquitto_sub", "-h", "localhost", "-p", "1883", "-t", "test", "-W", "1"]
+      test: ["CMD-SHELL", "bash -c 'cat < /dev/tcp/localhost/1883'"]
       interval: 30s
       timeout: 10s
       retries: 3