Basic ModelSettings logic

[sydney-runkle]

This PR adds support for a model_settings argument to run calls, as well as Agent initialization to specify model settings like temperature, timeout, etc. We anticipate further developing this structure in the future with more specs.

In the future, we'd consider adding a model_specific key to aid in specifying settings for specific models, like anthropic or openai

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[hyperlint-ai]

The style guide flagged several spelling errors that seemed like false positives. We skipped posting inline suggestions for the following words:

• [Ii]nherited_members

[hyperlint-ai]

2 files reviewed, 1 total issue(s) found.

[samuelcolvin]

Otherwise looking good. we need to add docs, and make sure all models are respecting all relevant settings.

[sydney-runkle]

@samuelcolvin,

What docs would you like me to add beyond the existing conceptual and API docs?

Apologies, I had an outdated comment in the description indicating docs were still needed, but I added some late yesterday.