`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`

Start by reproducing `gh skill install github/gh-stack` and tracing the interactive selection flow around the `? Filter skills` prompt. Verify the right-arrow, Space, and Enter sequence from the report, then confirm that selecting skills and pressing Enter completes installation without returning to the filter prompt.

Written by the indexing model from the issue text.