Use mistralai package instead of raw httpx to implement ChatMistralAI

[codefromthecrypt]

Checked

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Feature request

I'm interested in a variant or change to ChatMistralAI so that it uses the official SDK to implement it, similar to some of the other models. https://github.com/mistralai/client-python

Motivation

Particularly observability it difficult when official libraries aren't re-used. For example, via boto instrumentation we can collect logs, traces and metrics from bedrock. However, to do the same in ChatMistralAI involves quite a lot of work due to sharing no code with the official package. This makes it more difficult to support folks doing things like otel and/or evals via its format.__

Proposal (If applicable)

I'd prefer if ChatMistralAI was refactored to use the mistral SDK, or at least hear why in the case of Mistral AI this doesn't make sense vs others which already re-use official SDKs.