Disabled camera output (#16920)

* Fix live cameras not showing on refresh

* Fix live dashboard when birdseye is added

* Handle cameras that are offline / disabled

* Use black instead of green frame

* Fix missing mqtt topics

frigate/comms/mqtt.py

@@ -43,6 +43,11 @@ class MqttClient(Communicator):  # type: ignore[misc]
     def _set_initial_topics(self) -> None:
         """Set initial state topics."""
         for camera_name, camera in self.config.cameras.items():
+            self.publish(
+                f"{camera_name}/enabled/state",
+                "ON" if camera.enabled_in_config else "OFF",
+                retain=True,
+            )
             self.publish(
                 f"{camera_name}/recordings/state",
                 "ON" if camera.record.enabled_in_config else "OFF",
@@ -196,6 +201,7 @@ class MqttClient(Communicator):  # type: ignore[misc]
 
         # register callbacks
         callback_types = [
+            "enabled",
             "recordings",
             "snapshots",
             "detect",