pane: 'Close others' now closes relative to right-clicked tab (#34355)

Closes #33445

Fixed the "Close others" context menu action to close tabs relative to
the right-clicked tab instead of the currently active tab. Previously,
when right-clicking on an inactive tab and selecting "Close others", it
would keep the active tab open rather than the right-clicked tab.

## Before/After

https://github.com/user-attachments/assets/d76854c3-c490-4a41-8166-309dec26ba8a



## Changes

- Modified `close_inactive_items()` method to accept an optional
`target_item_id` parameter
- Updated context menu handler to pass the right-clicked tab's ID as the
target
- Maintained backward compatibility by defaulting to active tab when no
target is specified
- Updated all existing call sites to pass `None` for the new parameter

Release Notes:

- Fixed: "Close others" context menu action now correctly keeps the
right-clicked tab open instead of the active tab

crates/editor/src/editor_tests.rs

@@ -21465,7 +21465,7 @@ println!("5");
         .unwrap();
     pane_1
         .update_in(cx, |pane, window, cx| {
-            pane.close_inactive_items(&CloseInactiveItems::default(), window, cx)
+            pane.close_inactive_items(&CloseInactiveItems::default(), None, window, cx)
         })
         .await
         .unwrap();
@@ -21501,7 +21501,7 @@ println!("5");
         .unwrap();
     pane_2
         .update_in(cx, |pane, window, cx| {
-            pane.close_inactive_items(&CloseInactiveItems::default(), window, cx)
+            pane.close_inactive_items(&CloseInactiveItems::default(), None, window, cx)
         })
         .await
         .unwrap();