Improve importing font-family settings from VS Code (#39736)

Closes https://github.com/zed-industries/zed/issues/39259

- Fixes import of `editor.fontFamily` (we were looking for the wrong
key)
- Adds basic support for the CSS font-family syntax used by VS Code,
including font fallback

Release Notes:

- N/A
ef839cc207John Tur committed on 10/8/2025, 11:19:48 PM· committed by GitHubparent3d0312f
5 files changedLine totals unavailable