`gh skill install github/gh-stack` gets stuck in `? Filter skills` prompt

### Describe the bug
When running `gh skill install github/gh-stack`, pressing Enter at the interactive prompt repeatedly displays `? Filter skills` in a loop, making it impossible to proceed with the installation.

### Steps to reproduce
1. Run `gh skill install github/gh-stack`
2. Hit `` to select all
3. Hit `Enter`
4. It shows `? Filter skills` interactive prompt to appear
5. Press `Enter` again
6. It shows `Select skill(s) to install:` again. And the first entry been deselected. (See image 1)
7. I hit `Space` to select first entry. Then, hit `Enter`.
8. It goes back to `? Filter skills` again.
9. ...Infinite loop...

> image 1

Here is the video clips:

https://github.com/user-attachments/assets/e14d9cae-1f93-4cde-9b4a-ed732af0e989

### Expected behavior
The skill should be selected/installed, or standard interactive controls (e.g., Space to select, Enter to confirm) should complete the process without repeatedly looping back to the filter prompt.

### Actual behavior
It continuously reprompts `? Filter skills` upon hitting Enter and cannot proceed.

### Context / Environment
- Command: `gh skill install github/gh-stack`
- Tool: GitHub CLI (`gh`) / `gh-stack`

Beginne damit, `gh skill install github/gh-stack` zu reproduzieren und den interaktiven Auswahlablauf rund um die Eingabeaufforderung `? Filter skills` zu verfolgen. Überprüfe die im Bericht beschriebene Sequenz aus Pfeil nach rechts, Space und Enter und bestätige anschließend, dass die Auswahl von Skills und das Drücken von Enter die Installation abschließt, ohne zur Filtereingabeaufforderung zurückzukehren.

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