Some maintenance and minor fixes to state containers based on experience while working with them in elastic#53582

Patch unit tests to use current "terminology" (e.g. "transition" vs "mutation")
Fix docs where "store" was used instead of "state container"
Allow to create state container without transition.
Fix freeze function to deeply freeze objects.
Restrict State to BaseState with extends object.
in set() function, make sure the flow goes through dispatch to make sure middleware see this update
Improve type inference for useTransition()
Improve type inference for createStateContainer().

Other issues noticed, but didn't fix in reasonable time:
Can't use addMiddleware without explicit type casting elastic#54438
Transitions and Selectors allow any state, not bind to container's state elastic#54439