Add g/G (vi/less-style) navigation to +list-themes TUI

[bousii]

What do you want to change?

I am just trying out Ghostty on Linux, and I really liked the +list-themes TUI. I liked the j/k key and PageUp/PageDown navigation, and thought adding G/g for jumping to the top and bottom of the list would be a harmless addition to the controls in line with the controls that were inspired by vi/less already in the TUI.

Why do you want to make this change?

It would allow users of compact keyboards without Home or End keys, or users who are used to less or vi style commands to jump quickly across the list-themes TUI.

I acknowledge that:

• I have read the Contributing Guide and understand the contribution process.
• I have read and agree to follow the AI Usage Policy.
• I wrote this vouch request myself, in my own voice, without AI generating it.

[jcollie]

!vouch