Pasting output copied from copilot mangles the input area unrecoverably

### Describe the bug

I was just trying to paste something back to copilot it had generated and that paste destroyed the input bar. I had to exit, tried again and it also happened again. Also happened in a completely different terminal session on another machine.

### Affected version

GitHub Copilot CLI 1.0.69

### Steps to reproduce the behavior

1. Copy a line from a table produced in session
2. Paste that line
3. Observe broken input area

### Expected behavior

Input area should be able to handle input gracefully

### Additional context

_No response_

The issue identifies GitHub Copilot CLI 1.0.69 and a reproducible paste-from-table trigger. Start by reproducing the failure with a copied table line in the CLI, then trace the input-area handling for pasted content. Done means the input area remains usable after the paste and the reported reproduction no longer mangles it.

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