[Feature] supports custom session global variables (not displayed to users, maintained in workflow)

[TraceIvan]

MaxKB Version

v1.10.2

Please describe your needs or suggestions for improvements

希望能够自定义会话全局变量（不对用户展示，工作流中维护），从而在变量赋值节点中进行选择。目前变量赋值节点只能选择预定义的全局变量（当前时间、历史记录、会话ID）以及用户输入参数或接口传参（可自定义，但是用户可见，可由用户修改）。

Please describe the solution you suggest

No response

Additional Information

No response

[baixin513]

感谢反馈，后续考虑一下

[shaohuzhang1]

Bot detected the issue body's language is not English, translate it automatically. 👯👭🏻🧑‍🤝‍🧑👫🧑🏿‍🤝‍🧑🏻👩🏾‍🤝‍👨🏿👬🏿

---

Thanks for the feedback, please consider it later