Add launch flag to bypass trust folder prompt

When automating `copilot` CLI from scripts it would be very helpful to have a way to opt-in to trusting the folder via a launch flag so that the folder doesn't first have to be trusted via an interactive session and answering the prompt manually, or by directly editing the `~\.copilot\config.json` file.

I'm imagining something like:

```
$ copilot --trust-folder --allow-all-tools
```

Related #1121

从 copilot CLI 的启动参数处理开始，并阅读相关 issue #1121 以了解现有上下文。添加一个启动标志，使当前文件夹无需交互式提示即可被信任，包括与 --allow-all-tools 结合使用时。完成标准是：通过脚本启动时，无需编辑 config.json 或手动回答提示即可信任该文件夹。

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