debugger: Remember focused item (#30722)

Release Notes:

- Debugger Beta: the `debug panel: toggle focus` action now preserves
the debug panel's focused item.

crates/debugger_ui/src/debugger_panel.rs

@@ -69,15 +69,20 @@ pub struct DebugPanel {
 }
 
 impl DebugPanel {
-    pub fn new(workspace: &Workspace, cx: &mut Context<Workspace>) -> Entity<Self> {
+    pub fn new(
+        workspace: &Workspace,
+        _window: &mut Window,
+        cx: &mut Context<Workspace>,
+    ) -> Entity<Self> {
         cx.new(|cx| {
             let project = workspace.project().clone();
+            let focus_handle = cx.focus_handle();
 
             let debug_panel = Self {
                 size: px(300.),
                 sessions: vec![],
                 active_session: None,
-                focus_handle: cx.focus_handle(),
+                focus_handle,
                 project,
                 workspace: workspace.weak_handle(),
                 context_menu: None,
@@ -88,6 +93,24 @@ impl DebugPanel {
         })
     }
 
+    pub(crate) fn focus_active_item(&mut self, window: &mut Window, cx: &mut Context<Self>) {
+        let Some(session) = self.active_session.clone() else {
+            return;
+        };
+        let Some(active_pane) = session
+            .read(cx)
+            .running_state()
+            .read(cx)
+            .active_pane()
+            .cloned()
+        else {
+            return;
+        };
+        active_pane.update(cx, |pane, cx| {
+            pane.focus_active_item(window, cx);
+        });
+    }
+
     pub(crate) fn sessions(&self) -> Vec<Entity<DebugSession>> {
         self.sessions.clone()
     }
@@ -182,8 +205,8 @@ impl DebugPanel {
         cx: &mut AsyncWindowContext,
     ) -> Task<Result<Entity<Self>>> {
         cx.spawn(async move |cx| {
-            workspace.update(cx, |workspace, cx| {
-                let debug_panel = DebugPanel::new(workspace, cx);
+            workspace.update_in(cx, |workspace, window, cx| {
+                let debug_panel = DebugPanel::new(workspace, window, cx);
 
                 workspace.register_action(|workspace, _: &ClearAllBreakpoints, _, cx| {
                     workspace.project().read(cx).breakpoint_store().update(