CreateChat 使用stream字段判断是否为流式对话，data为http请求体， 模型侧接口统一使用post请求，故使用any类型承接请求体兼容模型侧的不同api.

NoStreamChat 创建非流式回答，data为请求体.

LLMAnswer 模型返回的结果，在 非流式的格式中模型返回的消息在 LLMAnswer.choices[index].message.content中 流式的格式中模型返回的消息在 LLMAnswer.choices[index].delta.content中 非流式 { "id": "string", "object": "string", "created": 0, "model": "string", "choices": [ { "index": 0, "message": { "role": "string", "content": "string" }, "finish_reason": "string" } ], "usage": { "prompt_tokens": 0, "completion_tokens": 0, "total_tokens": 0 }, "corr_lst": [ "string" ], "code": 0 } 流式 { "id": "string", "object": "string", "created": 0, "model": "string", "choices": [ { "index": 0, "delta": { "role": "string", "content": "string" }, "finish_reason": "string", "usage": { "prompt_tokens": 0, "completion_tokens": 0, "total_tokens": 0 } } ], "corr_lst": [ "string" ], "code": 0 }.