Merge changes Ib09d61eb,I2678c1d2,I125610c1,I554517b7,I48e12cdb, ... into main

* changes:
  Remove the fork of STL UserActionResult
  Remove the Communal fork of STL ObservableTransitionState
  Remove the fork of STL ObservableTransitionState
  Remove the fork of STL TransitionKey
  Remove the Communal fork of STL SceneKey
  Remove the fork of STL SceneKey
  Rename CommunalSceneKey.Foo to CommunalScenes.Foo
  Rename SceneKey.Foo to Scenes.Foo