Cross-app session sync between Copilot CLI and Copilot Desktop App

### Describe the feature or problem you'd like to solve

I use both the GitHub Copilot CLI and the Copilot desktop app on macOS. Currently, sessions started in the CLI are not visible or accessible in the desktop app, and vice versa. It would be very useful to have sessions synced (or at least importable/resumable) across both interfaces, so I can seamlessly switch between a terminal and desktop workflow without losing context. Suggested improvements: • Show CLI sessions in the desktop app's session list • Allow resuming a CLI session from the desktop app (and vice versa) • Or at minimum, a one-click export/import between the two

### Proposed solution

_No response_

### Example prompts or workflows

_No response_

### Additional context

_No response_

从 Copilot CLI 的会话和恢复入口以及 macOS 桌面应用的会话列表开始。比较每个界面如何展示会话，然后确定同步还是一键导入/导出更适合该工作流。当会话可以在两个界面中被发现并恢复，或在两者之间传输时，即视为完成。

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