Start work on autocomplete for chat mentions

Co-authored-by: Conrad <conrad@zed.dev>
Co-authored-by: Nathan <nathan@zed.dev>
Co-authored-by: Marshall <marshall@zed.dev>
139986d080Max Brunsfeld committed on 1/19/2024, 9:12:57 PMparent1ceccdf
6 files changedLine totals unavailable