M8-R01: add configurable MQTT client identity

app/api/routes/api/config.py

@@ -9,7 +9,7 @@ from sqlalchemy.orm import Session
 from app.api.routes.api.deps import require_csrf, require_session
 from app.config import Settings, get_settings
 from app.dependencies import get_app_settings, get_db
-from app.integrations.mqtt import MQTT_SETTINGS_KEYS, mqtt_manager
+from app.integrations.mqtt import MQTT_SETTINGS_KEYS, mqtt_manager, mqtt_test_client_id
 from app.schemas.config import (
     ConfigField,
     ConfigResponse,
@@ -233,7 +233,7 @@ def _run_mqtt_test(settings: Settings) -> None:
 
     client = mqtt.Client(
         callback_api_version=mqtt.CallbackAPIVersion.VERSION2,
-        client_id="home-automation-test",
+        client_id=mqtt_test_client_id(settings.mqtt_client_id),
     )
 
     def _on_connect(