Implement call method for elements in CDGA's

[miguelmarco]

Fixes #36328 by implementing the method.

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[tscrim]

While I am not 100% sure we should force the user to pass in every value, it is consistent with the multivariate polynomial ring.

I would also avoid code duplication for dict input and keyword input and just combine the two and go from there.

Having things made explicit in the doc about mixing input types and the expected behavior could be useful later on.

[tscrim]

By this point, you have not used/parsed the keywords. So if someone passes in a mixture, then this might give a false result. In general, you probably should at least document the behavior and what you expect to have happen.

[miguelmarco]

I would also avoid code duplication for dict input and keyword input and just combine the two and go from there.

This is in some sense unavoidable, since in the case of dict, the keys are elements of the algebra, whereas in the case of keywords, the keys are strings. We could try to unify them, but then we would need code for that. It won't be really better than having two five-line loops that are close to duplicated.

[tscrim]

I probably would just make every dict comparison done by strings, but okay, let it be so once a few other very minor changes are done.

[tscrim]

Thank you.

If you could just squash the (reviewer changes) commits, then it will be a positive review.

[miguelmarco]

done!

[github-actions]

Documentation preview for this PR (built with commit 320f177; changes) is ready! 🎉

[tscrim]

Thank you.