Update pydantic version & fix mypy errors

[srjoglekar246]

Why are these changes needed?

Fix some recently introduced mypy errors & also bump pydantic version so that warnings related to model_ fields go away without code changes.

Checks

• poe test seems to pass locally.
• pydantic warnings go away after version bump.

[srjoglekar246]

@jackgerrits @ekzhu Trying to fix some pydantic & mypy issues here.

I updated uv.lock as the error suggested, but could you double-check that the diff is okay at a high level?

[srjoglekar246]

@jackgerrits / @ekzhu Could you double-check if uv sync --locked --all-extras is actually causing issues as mentioned in the CI errors above? Weirdly on my local setup I don't see any issues, and theres no diff I see when I do uv lock. Am I missing something?

[ekzhu]

Could you revert your changes to the lock file to the main branch version, and then, you generate a new one by calling uv sync --all-extras, followed by uv lock to generate a new lock file.