Increase min-width for all Pickers, minor style changes

- Increases the Picker min-width from 500 to 540
- Makes some changes to the styling of keyboard shortcuts in the command palette

crates/picker/src/picker.rs

@@ -138,7 +138,7 @@ impl<D: PickerDelegate> Picker<D> {
             list_state: Default::default(),
             update_task: None,
             delegate,
-            max_size: vec2f(500., 420.),
+            max_size: vec2f(540., 420.),
             confirmed: false,
         };
         cx.defer(|this, cx| this.update_matches(cx));