git_panel: Fix focus navigation across Changes and History (#62215)

# Objective

Fix several Git panel focus issues:

- Directional navigation could not move focus into the History tab.
- History focus state was not updated when the panel received focus.
- Switching back to Changes could leave focus on the panel instead of
the commit editor.

Fixes #62211


## Solution

- Use the Git panel root as the activation focus target when History is
active.
- Reuse the panel's focus handle for focus events.
- Use the appropriate activation target when switching tabs.


## Testing

- Add a regression test
`test_history_tab_pane_navigation_focuses_rendered_panel` for navigating
between the editor and History.

## Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content adheres to Zed's UI standards
([UX/UI](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
and
[icon](https://github.com/zed-industries/zed/blob/main/crates/icons/README.md)
guidelines)
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

## Showcase

after fix:

[2026-08-05
22-45-38.webm](https://github.com/user-attachments/assets/fdb3f87a-f1af-4ae1-95f7-0d61acfb3095)



---

Release Notes:

- Fixed directional focus navigation into the Git panel's History tab.

crates/git_ui/src/git_panel.rs

@@ -1222,7 +1222,7 @@ impl GitPanel {
                 view_mode: GitPanelViewMode::from_settings(cx),
                 tree_expanded_dirs: HashMap::default(),
                 projected_entries_by_path: HashMap::default(),
-                focus_handle: cx.focus_handle(),
+                focus_handle,
                 fs,
                 new_count: 0,
                 new_staged_count: 0,
@@ -6306,13 +6306,12 @@ impl GitPanel {
             return;
         }
         self.active_tab = tab;
+        self.activation_focus_handle(cx).focus(window, cx);
         match tab {
             GitPanelTab::History => {
-                self.focus_handle.focus(window, cx);
                 self.load_commit_history(cx);
             }
             GitPanelTab::Changes => {
-                self.focus_handle.focus(window, cx);
                 self.set_commit_history(CommitHistory::Loading, cx);
                 self._repo_subscriptions.clear();
             }
@@ -8201,7 +8200,9 @@ impl editor::Addon for GitPanelAddon {
 
 impl Panel for GitPanel {
     fn activation_focus_handle(&self, cx: &App) -> FocusHandle {
-        if self.entries.is_empty() || self.commit_editor_expanded {
+        if self.active_tab == GitPanelTab::Changes
+            && (self.entries.is_empty() || self.commit_editor_expanded)
+        {
             self.commit_editor.focus_handle(cx)
         } else {
             self.focus_handle.clone()
@@ -8809,7 +8810,10 @@ mod tests {
     use util::path;
     use util::rel_path::rel_path;
 
-    use workspace::{MultiWorkspace, ToolbarItemEvent, ToolbarItemLocation};
+    use workspace::{
+        ActivatePaneLeft, ActivatePaneRight, MultiWorkspace, ToolbarItemEvent, ToolbarItemLocation,
+        item::test::TestItem,
+    };
 
     use super::*;
 
@@ -12451,6 +12455,54 @@ mod tests {
         });
     }
 
+    #[gpui::test]
+    async fn test_history_tab_pane_navigation_focuses_rendered_panel(cx: &mut TestAppContext) {
+        init_test(cx);
+
+        let (_, _project, workspace, panel, mut cx) =
+            setup_git_panel_with_changes(cx, json!({ ".git": {} }), &[]).await;
+
+        let center_item = workspace.update_in(&mut cx, |workspace, window, cx| {
+            let center_item = cx.new(TestItem::new);
+            workspace.add_item_to_active_pane(
+                Box::new(center_item.clone()),
+                None,
+                true,
+                window,
+                cx,
+            );
+            workspace.add_panel(panel.clone(), window, cx);
+            workspace.open_panel::<GitPanel>(window, cx);
+            center_item
+        });
+        panel.update_in(&mut cx, |panel, window, cx| {
+            assert!(panel.entries.is_empty());
+            panel.activate_history_tab(&ActivateHistoryTab, window, cx);
+        });
+        center_item.update_in(&mut cx, |center_item, window, cx| {
+            center_item.focus_handle(cx).focus(window, cx);
+        });
+        cx.run_until_parked();
+
+        cx.dispatch_action(ActivatePaneRight);
+        cx.run_until_parked();
+
+        let history_panel_was_focused = panel.update_in(&mut cx, |panel, window, cx| {
+            panel.focus_handle.contains_focused(window, cx)
+        });
+
+        cx.dispatch_action(ActivatePaneLeft);
+        cx.run_until_parked();
+
+        let center_item_is_focused = center_item.update_in(&mut cx, |center_item, window, cx| {
+            center_item.focus_handle(cx).is_focused(window)
+        });
+        assert!(
+            history_panel_was_focused && center_item_is_focused,
+            "pane navigation should focus the History panel after moving right and restore the center item after moving left; History panel focused after moving right: {history_panel_was_focused}, center item focused after moving left: {center_item_is_focused}"
+        );
+    }
+
     #[gpui::test]
     async fn test_discard_tracked_changes_respects_staging(cx: &mut TestAppContext) {
         init_test(cx);