[Feature Request] 可否支持自定义所有模型的系统级提示信息？

[Silypie]

🥰 需求描述

发现一个问题：有些模型（比如Gemini flash）经常使用英文回答。即使在设置中勾选了“注入系统级提示信息”，发送请求的时候载荷里也没有相关的提示信息。

🧐 解决方案

如果可以自定义系统级提示信息或者用户的第一条信息就好了

📝 补充信息

No response

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Title: [Feature Request] Can you support customizing system-level prompt information for all models?

🥰 Description of requirements

Found a problem: some models (such as Gemini flash) often answer in Chinese. Even if "Inject system-level prompt information" is checked in the settings, there is no relevant prompt information in the payload when sending the request.

🧐 Solution

It would be great if you could customize the system-level prompt message or the user's first message

📝 Supplementary information

No response