openai.ChatCompletionRequest 序列化删除空值Stream参数导致无法开启非流模式

[hfutkang]

后端大模型默认是流式模式，但是由于openai.ChatCompletionRequest的json标签使用了omitempty，序列化会删除空值，如果设置Stream=false，序列化时会被删除，导致传递给大模型接口的Body没有Stream参数，无法开启非流模式。
type ChatCompletionRequest struct {
Model string json:"model"
Messages []ChatCompletionMessage json:"messages"
// MaxTokens The maximum number of tokens that can be generated in the chat completion.
// This value can be used to control costs for text generated via API.
// Deprecated: use MaxCompletionTokens. Not compatible with o1-series models.
// refs: https://platform.openai.com/docs/api-reference/chat/create#chat-create-max_tokens
MaxTokens int json:"max_tokens,omitempty"
// MaxCompletionTokens An upper bound for the number of tokens that can be generated for a completion,
// including visible output tokens and reasoning tokens https://platform.openai.com/docs/guides/reasoning
MaxCompletionTokens int json:"max_completion_tokens,omitempty"
Temperature *float32 json:"temperature,omitempty"
TopP float32 json:"top_p,omitempty"
N int json:"n,omitempty"
Stream bool json:"stream,omitempty"
Stop []string json:"stop,omitempty"
}