chore(backend/__init__.py): add Client and ClientStatus to __all__

src/judas_server/backend/__init__.py

@@ -1,3 +1,5 @@
 from .backend_server import BackendServer
+from .client import Client
+from .client_status import ClientStatus
 
-__all__ = ["BackendServer"]
+__all__ = ["BackendServer", "Client", "ClientStatus"]