refactor(connection): public protocol_active accessor replaces the remote entity's private reach-in; media_player module docstring describes the Phase 2 architecture (F7)

custom_components/nvidia_shield/remote.py

@@ -101,7 +101,7 @@ class NvidiaShieldRemoteEntity(RemoteEntity):
         manager = self._manager_of()
         if not isinstance(manager, ShieldConnectionManager):
             return True
-        if manager._protocol is None:
+        if not manager.protocol_active:
             return True
         return manager.is_available is not False