fix for pydantic tool calling with a single argument

[logan-markewich]

Pydantic classes/tools will not work with positional arguments, so we need some kind of fallback to handle this case.

Fixes #13518

[nerdai]

Looks good. Only thing I wonder is if there is a specific Exception we can catch that leads to trying with "kwargs" execution.

[logan-markewich]

I think there could be a specific pydantic error to catch, but I casted a wider net to ensure bases were covered beyond pydantic 😅

[nerdai]

Makes sense to me. Thanks!