Integrate Apalache Chai

[ivan-gavran]

Currently, for interacting cleanly with Apalache, we use modelator-py.
However, recently, Apalache introduced the server mode called Chai. Chai would give us the same functionality as modelator-py but would be more robust and standardized (ie, we would not depend on hacky parsing of CLI output).

[shonfeder]

Let me know if I can offer support here.

[shonfeder]

I have suggested to several interested parties, that we use this issue to gather links and references that serve as evidence to show the business case that would motivate us prioritizing this work.