Selection: Cmd/Ctrl over a centre point selects behind, so the arrow stays plain

The press with Cmd/Ctrl held selects the object behind rather than taking the
centre point; the pointer now agrees.

crates/tools/src/select.rs

@@ -1133,8 +1133,9 @@ impl Tool for SelectionTool {
         }
         // A selected object's centre point (Show Center): a press there moves it, where the art
         // may not reach. The box's handles and the ruler guides take a press before it, so they
-        // take the pointer too (on a thin box the centre lies within a handle's reach).
-        if near_selected && hit_center(cx, p, cx.point_tol()).is_some() {
+        // take the pointer too (on a thin box the centre lies within a handle's reach), and with
+        // Cmd/Ctrl held the press selects the object behind instead.
+        if near_selected && !m.cmd && hit_center(cx, p, cx.point_tol()).is_some() {
             return Cursor::Move;
         }
         // View → Snap to Point: over an anchor a press would grab the object by, the arrow turns

crates/tools/src/select/tests.rs

@@ -2153,6 +2153,8 @@ fn a_press_on_the_centre_point_moves_an_unfilled_shape() {
     let centre = Point::new(150.0, 150.0);
     let mut t = SelectionTool::default();
     assert_eq!(t.cursor(&c, centre, Mods::default()), Cursor::Move);
+    // Cmd/Ctrl selects the object behind, not the centre point, so the pointer says neither.
+    assert_ne!(t.cursor(&c, centre, Mods { cmd: true, ..Mods::default() }), Cursor::Move);
     assert!(t.pointer(&c, &ev(PointerKind::Down, centre.x, centre.y)).is_empty());
     let a = t.pointer(&c, &ev(PointerKind::Drag, 170.0, 160.0));
     assert_eq!(a.first(), Some(&Action::Begin("Move".into())), "{a:?}");