Feature: Importing Stately.AI code

[RicoFio]

Summary

Hi there! First of all, thanks a lot for the great library!

It would be great if it was possible to load Stately.AI JSON objects at runtime (or convert them to executable code). That way, one could allow users to design their state machine with Stately.AI and using them in-code.

Acceptance criteria

• There is a method to read in JSON files generated using Stately.AI and either:
  • generate automata Dart code or
  • load an object during runtime which can iterate through the states using the indicated actions in the state automaton JSON