M8-R15: fix HA discovery identities and thermal totals

app/integrations/mqtt.py

@@ -174,23 +174,33 @@ class MqttManager:
         *,
         retain: bool = False,
         qos: int = 0,
-    ) -> None:
+    ) -> bool:
         """Publish a message to *topic*.
 
-        If the client is not connected the call is silently skipped.
-        Errors are logged but do not raise.
+        Return whether paho accepted the message for publication.  If the
+        client is not connected, or paho raises/rejects it, return ``False``;
+        errors still do not escape this best-effort boundary.
         """
         with self._lock:
             client = self._client
 
         if client is None or not self._connected:
             logger.debug("MQTT publish skipped — not connected (topic=%s).", topic)
-            return
+            return False
 
         try:
-            client.publish(topic, payload=payload, qos=qos, retain=retain)
+            result = client.publish(topic, payload=payload, qos=qos, retain=retain)
+            # paho returns MQTTMessageInfo with an integer rc.  Keep fakes and
+            # alternate clients compatible by treating an absent/non-int rc as
+            # accepted after the call itself succeeded.
+            rc = getattr(result, "rc", None)
+            if isinstance(rc, int) and rc != mqtt.MQTT_ERR_SUCCESS:
+                logger.warning("MQTT publish rejected (topic=%s, rc=%s).", topic, rc)
+                return False
+            return True
         except Exception:
             logger.exception("MQTT publish error (topic=%s).", topic)
+            return False
 
     def subscribe(self, topic: str, handler: Callable[[bytes], None]) -> None:
         """Register *handler* to be called when a message arrives on *topic*.