C-53: Improve PilotUISyncer class naming

[doridori]

PilotUISyncer is a rubbish name as it is not clear what it is doing.

StateStackRenderer would be more descriptive.

This is composed of various classes that handle a subset of states. The interface for these could be called StatesRenderer and implementations could be called RenderStatesToView, RenderStatesToDialog, RenderStatesToFragment etc.

Easier to work out what the above is doing from the class name for the above.