Most hated keyboard shortcut: CTRL + Z - Copilot CLI says: Goodbye! (green)

### Describe the bug

Every writer, every developer is typing, copying, pasting and undoing and redoing.

First of all copy and paste does NOT work in Copilot. Please refer to other issues.

What happens?
When i select a peace of text outside the CLI, or from another Copilot CLI and right mouse to paste in Copilot CLI (or CTRL +C and CTRL + V), is does NOT work. I paste something old from clipboard, not what i just copied.

Then i use CTRL + Z to undo. This is automatic behavior, 1 millions of people do every day.
I don't want the wrong pasted text. And what happens? Copilot says: Goodbye and exits. I hate this so much!

The only reason i use Copilot CLI is for the auto mode of models and control my models, budgets and policies in github. If Claude CLI or Gemini CLI ever support other models in their future releases then their own, i would switch forever and never use Copilot CLI again. I really hate it.

Please remove the CTRL+Z shortcut or fix it. I lost so many conversations.

ps. On linux it says: please use fq to return to the session. That also doesnt work.

Please fix this very very very anyoing bug!

### Affected version

_No response_

### Steps to reproduce the behavior

_No response_

### Expected behavior

_No response_

### Additional context

_No response_

首先在 Copilot CLI 中复现 Ctrl+Z 的退出行为，以及报告中提到的复制/粘贴和使用 `fq` 返回会话的行为，尤其是在 Linux 上。检查 CLI 对键盘快捷键和会话输入的处理；当 Ctrl+Z 不再意外退出，并且文档所述的返回会话行为正常工作时，即可视为完成。

由索引模型根据 Issue 内容生成。