make chat completion json_response any

[yang-wei]

Is your feature request related to a problem? Please describe.

Many OpenAI alternatives (such as anyscale) currently support response_format.schema in ChatCompletion request. The syntax looks like

    response_format={
        "type": "json_object", 
        "schema": Result.schema_json()
    },

under the hood, the library that supports this validates the response and re-prompt the LLM if it doesn't follow the schema response. I understand that this library only implements what OpenAI support that's why my request is to use any for response_format type rather than ChatCompletionResponseFormat

Describe the solution you'd like
use any for ResponseFormat type instead of ChatCompletionResponseFormat which follows openAI spec (which is object)

https://github.com/sashabaranov/go-openai/blob/eff8dc1118ea82a1b50ee316608e24d83df74d6b/chat.go#L196C20-L196C48

Additional context
Happy to send a PR if this is something @sashabaranov think it makes sense

[comzine]

This is not needed due to the new JSON mode:
https://platform.openai.com/docs/guides/text-generation/json-mode
But this JSON mode should be supported here 😊