llms: implement StreamingReasoningFunc for reasoning models

[douglarek]

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[tmc]

Thanks for your contribution! Can you follow on with an example please?

[douglarek]

Thanks for your contribution! Can you follow on with an example please?

Okay, the deepseek example has been reused.

[tmc]

Wups I merged this prematurely.

[Hades32]

did you test this with OpenAI? From my testing they fail when the temperature parameter is not removed. See #1129

[douglarek]

did you test this with OpenAI? From my testing they fail when the temperature parameter is not removed. See #1129

This is a merged PR, please open a new issue for discussion.