Investigate integrating libghostty

[juliusmarminge]

xterm currently serves us well but should eventually look into exploring libghostty

https://x.com/mitchellh/status/2035382831237714422?s=46

[AllenThomasDev]

btw there is a drop-in replacement for xterm based on ghostty - https://github.com/coder/ghostty-web

[PixPMusic]

The mobile apps getting libghostty made me jealous.

ghostty-web is *mostly a drop-in replacement for xterm.js.

[PixPMusic]

I do see there's also work on a non-wrappered version: #4860, however, the Canvas renderer has no Nerd Font fallback. FONT_FAMILY contains only regular monospace faces, so common prompt glyphs and devicons render as missing characters.

My PR (#3820) adds loading of the ghostty config, which may or may not be a feature wanted in the final product.
I do include a Nerd Font in my PR, as I did on Android, to enable glyph support in the mobile terminal.