Fix assorted linux issues (#10061)

- Fix a bug where modifiers would be dispatched before they changed
- Add a secondary modifier
- Improve keybindings

Release Notes:

- N/A

crates/ui/src/components/keybinding.rs

@@ -113,7 +113,7 @@ impl RenderOnce for KeyBinding {
                             el.child(Key::new("Alt")).child(Key::new("+"))
                         }
                     })
-                    .when(keystroke.modifiers.command, |el| {
+                    .when(keystroke.modifiers.platform, |el| {
                         match self.platform_style {
                             PlatformStyle::Mac => el.child(KeyIcon::new(IconName::Command)),
                             PlatformStyle::Linux => {