feat(v7): get_evaluation_result

[khvn26]

Contributes to #234.

For now, the PR maintains full backwards compatibility. Hopefully, we'll be able to release V7 without the old interfaces and models altogether. This should allow us do ditch the Pydantic dependency. Worst case scenario, get_environment_feature_state[s]/get_identity_feature_state[s] will stay but produce a DeprecationWarning.

I've started some threads to add my own notes on the code, everybody's welcome to add comments there.

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Generated by 🐒 cobertura-action against d1f6414

[Zaimwa9]

One NIT on my side, otherwise looks like we are reaching the end. Updated mappers in python-client accordingly

[Zaimwa9]

👍

[matthewelwell]

As per request from @khvn26 I have retrospectively reviewed the code. While I think there are sections which are quite complex, I can definitely see some of the benefits starting to appear. Looks good!