M5: use DB-merged runtime settings for MQTT/discovery; add MQTT test button; move Expose panel into config accordion

app/services/ha_discovery.py

@@ -35,6 +35,7 @@ from sqlalchemy.orm import Session
 
 from app.integrations.expose import ExposableEntity, build_catalog
 from app.integrations.mqtt import mqtt_manager
+from app.services.config_page import build_runtime_settings
 
 logger = logging.getLogger(__name__)
 
@@ -44,12 +45,6 @@ logger = logging.getLogger(__name__)
 # ---------------------------------------------------------------------------
 
 
-def _get_settings() -> Any:
-    """Return the current runtime settings (cached singleton)."""
-    from app.config import get_settings
-    return get_settings()
-
-
 def _should_publish(settings: Any) -> bool:
     """Return True only if MQTT and HA Discovery are both enabled and connected."""
     return bool(
@@ -180,7 +175,8 @@ def publish_discovery(session: Session) -> None:
     No-op if MQTT / discovery is not enabled or the client is not connected.
     All MQTT errors are caught internally — this function never raises.
     """
-    settings = _get_settings()
+    from app.config import get_settings
+    settings = build_runtime_settings(session, get_settings())
     if not _should_publish(settings):
         logger.debug("publish_discovery: skipped (MQTT/Discovery not enabled or not connected)")
         return
@@ -232,7 +228,8 @@ def publish_states(session: Session) -> None:
     No-op if MQTT / discovery is not enabled or the client is not connected.
     All errors are caught internally — this function never raises.
     """
-    settings = _get_settings()
+    from app.config import get_settings
+    settings = build_runtime_settings(session, get_settings())
     if not _should_publish(settings):
         logger.debug("publish_states: skipped (MQTT/Discovery not enabled or not connected)")
         return
@@ -320,7 +317,8 @@ def publish_device_state(session: Session, device: Any) -> None:
     No-op if MQTT / discovery is not enabled or the client is not connected.
     All errors are caught internally — never raises.
     """
-    settings = _get_settings()
+    from app.config import get_settings
+    settings = build_runtime_settings(session, get_settings())
     if not _should_publish(settings):
         return
 
@@ -386,7 +384,7 @@ def publish_device_state(session: Session, device: Any) -> None:
             )
 
 
-def publish_device_offline(device_uuid: str) -> None:
+def publish_device_offline(session: Session, device_uuid: str) -> None:
     """Publish an "offline" availability payload for *device_uuid*.
 
     Called by ``modbus_poll.poll_device`` when a poll fails, to immediately
@@ -395,7 +393,8 @@ def publish_device_offline(device_uuid: str) -> None:
     No-op if MQTT / discovery is not enabled or the client is not connected.
     Never raises.
     """
-    settings = _get_settings()
+    from app.config import get_settings
+    settings = build_runtime_settings(session, get_settings())
     if not _should_publish(settings):
         return
 

app/services/modbus_poll.py

@@ -132,7 +132,7 @@ def poll_device(session: Session, device: ModbusDevice) -> ModbusReading | None:
 
         # Best-effort: publish "offline" availability after failed poll.
         try:
-            publish_device_offline(device.uuid)
+            publish_device_offline(session, device.uuid)
         except Exception:  # noqa: BLE001
             logger.exception(
                 "poll_device: MQTT offline publish failed for device %r (id=%d)",