feat(ai): allow customizing all providers' base_url

[ImSingee]

I think this is useful for several reasons:

1. It's possible to use any unofficial services with OpenAI responses or the claude API format
2. For Codestral, it's possible to use the official free version (https://codestral.mistral.ai)

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Because the Resources' definition isn't included in the code (it's synced from the hub), this PR can't modify it.

[centdix]

I think this is useful for several reasons:

1. It's possible to use any unofficial services with OpenAI responses or the claude API format
2. For Codestral, it's possible to use the official free version (https://codestral.mistral.ai)

Because the Resources' definition isn't included in the code (it's synced from the hub), this PR can't modify it.

Hi, thanks for the PR. Why would using custom provider not be enough to be able to use any base_url ?

[ImSingee]

@centdix Just as my previous said, the custom provider can only provide /chat/completion API, but others are still valable

[centdix]

@centdix Just as my previous said, the custom provider can only provide /chat/completion API, but others are still valable

Hi, coming back to this, I'm adding support for it in one of my PR, thanks for the suggestion !