Rework CAtom_setstate

[frmdstryr]

Any suggestions for improvements are welcome:

1. PyMapping_Check is kind of broken so tuples and lists pass it
2. As mentioned in the other PR setattr triggers notifications
3. I don't like how it modifies the passed in state by deleting the frozen flag but checking every key makes it a lot slower (~30%)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.67%. Comparing base (54adc3f) to head (cf0d164).

Additional details and impacted files

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  Lines        1074     1074           
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  Misses         12       12           
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[MatthieuDartiailh]

The transition to c++ was done in https://github.com/nucleic/atom/pull/182/files#diff-e9ee00a921e9e460fd604a1d6fa1541ee97e2767aac2f335dd1448567d9d6ebfL648-L658 and we simply copied what existed on the Python side. When unpickling an object (I do not consider other possible abuse of __setstate__) the only observer that may be called are static observers. We could change this but it may be a breaking change.

[sccolbert]

I think I may have been lazy when implementing get/set state back in the day, just to get it out the door.

I think it's reasonable to assume that a call to __setstate__ would not trigger observers, since it's primary use is de-pickling.

But as you say, that might be a breaking change. Another thing that I would do very differently if afforded the opportunity.

[MatthieuDartiailh]

LGTM but can you investigate the Python 3.13 failure