Fix syntax highlighting of git commit messages (#26988)

- Load syntax colors into commit message editors
- Fix name mismatches that were preventing the git commit grammar and
language config from being matched up

Release Notes:

- Fixed git commit messages not being syntax-highlighted

crates/panel/src/panel.rs

@@ -113,6 +113,7 @@ pub fn panel_editor_style(monospace: bool, window: &Window, cx: &App) -> EditorS
             line_height: line_height.into(),
             ..Default::default()
         },
+        syntax: cx.theme().syntax().clone(),
         ..Default::default()
     }
 }