keymap_ui: Support unbinding non-user defined keybindings (#34318)
Closes #ISSUE
Makes it so that `KeymapFile::update_keybinding` treats removals of
bindings that weren't user-defined as creating a new binding to
`zed::NoAction`.
Release Notes:
- N/A *or* Added/Fixed/Improved ...
206cce6783Ben Kunkle committed on 7/11/2025, 9:23:14 PM· committed by GitHubparentc3edc2c