Provide missing generics for classmethod in create_model

[max-muoto]

Change Summary

Currently the typing for create_model leads to unknowns, possibly raising errors for Pyright users. This is because classmethod is a generic class, and we're simply not passing in any generic parameters for it.

This PR fixes the Pyright errors here by passing in generics for usages of classmethod here. My presumption is that the validator does not have to return the same type as it accepts, but if that assumption is wrong, I can switch this to use generics for first argument/return value. I use ... for the second value since it's simply a ParamSpec, and we don't really have a way to signify it takes in a singular argument unless we want to switch this to use Callable.

Checklist

• The pull request title is a good summary of the changes - it will be used in the changelog
• Unit tests for the changes exist
• Tests pass on CI
• Documentation reflects the changes where applicable
• My PR is ready to review, please add a comment including the phrase "please review" to assign reviewers

Selected Reviewer: @samuelcolvin

[codspeed-hq]

CodSpeed Performance Report

Merging #9338 will not alter performance

_{Comparing max-muoto:improve-create-model-typing (688ae29) with main (c4d2edc)}

Summary

✅ 13 untouched benchmarks

[max-muoto]

please review

[sydney-runkle]

Great, thanks! Your assumption re validators is correct :).

[max-muoto]

Great, thanks! Your assumption re validators is correct :).

Thanks for the review!