Open keymap editor from command palette entry (#40825)

Release Notes:

- Adds footer to the command palette with buttons to add or change the
selected actions keybinding. Both open the keymap editor though the add
button takes you directly to the modal for recording a new keybind.


https://github.com/user-attachments/assets/0ee6b91e-b1dd-4d7f-ad64-cc79689ceeb2

---------

Co-authored-by: Joseph T. Lyons <JosephTLyons@gmail.com>
Co-authored-by: Julia Ryan <juliaryan3.14@gmail.com>
Co-authored-by: Danilo Leal <daniloleal09@gmail.com>

crates/ui/src/components/keybinding.rs

@@ -68,6 +68,18 @@ impl KeyBinding {
     pub fn for_action_in(action: &dyn Action, focus: &FocusHandle, cx: &App) -> Self {
         Self::new(action, Some(focus.clone()), cx)
     }
+    pub fn has_binding(&self, window: &Window) -> bool {
+        match &self.source {
+            Source::Action {
+                action,
+                focus_handle: Some(focus),
+            } => window
+                .highest_precedence_binding_for_action_in(action.as_ref(), focus)
+                .or_else(|| window.highest_precedence_binding_for_action(action.as_ref()))
+                .is_some(),
+            _ => false,
+        }
+    }
 
     pub fn set_vim_mode(cx: &mut App, enabled: bool) {
         cx.set_global(VimStyle(enabled));