[Feature Request] Add setting for changing launch Mode for all chats - Interactive vs. Autopilot

### Feature summary

Add new settings under Sessions

### What problem are you trying to solve?

* I find myself starting new chat sessions, and the mode is always default to "Interactive".
* I'd love for this to be a setting so I can configure it to be "Autopilot" by default for all new chats.

### Proposed solution

* A new setting under Sessions (similar to default Model setting) could be a god-send.

### Workflow impact

Make it one less quick when starting new chats.

### Installation context

_No response_

### Additional context

_No response_

从 Sessions 设置开始，将建议的选项与现有的默认 Model 设置进行比较。跟踪新聊天如何在 Interactive 和 Autopilot 之间进行选择，然后验证所选设置是否控制每个新创建聊天的模式。

由索引模型根据 Issue 内容生成。