The "No, and tell copilot what to do option" isn't clear

### Describe the bug

I consider this a UX bug.

When copilot wants to execute some command, (e.g., code edits), it'll give an option like, "No, and tell copilot what to do instead".

In previous versions, selecting that option would just return you to the normal prompt mode, and you'd type the alternative. I think this is how the one installed via npm worked.

In the latest `Copilot v1.0.68`, when you select that menu option either by pressing the number or navigating with the arrow keys and pressing enter, nothing happens.

Only through sheer frustration at a color scheme regression this morning during which I randomly typed a flurry of keys on the keyboard this morning did I discover that the intent is to select that option and type the alternative instructions directly in the menu.

That was not easily discoverable.

### Affected version

GitHub Copilot CLI 1.0.68. Run 'copilot update' to check for updates.

### Steps to reproduce the behavior

The description explains this already

### Expected behavior

Something to clearly indicate where the input is supposed to happen

### Additional context

_No response_

Reproduce the menu behavior in GitHub Copilot CLI v1.0.68 using the numbered and arrow-key selections described in the issue. Trace the prompt/menu entry point and make the alternative-input affordance clear; done means users can tell where to type and the option behaves as expected.

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