A callback that can be populated to be notified when the client-authority state of objects changes.
Whenever an object is spawned using SpawnWithClientAuthority, or the client authority status of an object is changed with AssignClientAuthority or RemoveClientAuthority, then this callback will be invoked.
This callback is used by the NetworkMigrationManager to distribute client authority state to peers for host migration. If the NetworkMigrationManager is not being used, this callback does not need to be populated.