feat(ui): Select Other — pick what lies under something else (#503)

Hold the left button still (long-press on touch) or right-click › Select Other… to list everything under the cursor: sketch points and curves ("Line 3", "Point (arc 2 centre)"), vertices, edges, faces, bodies, profiles, planes and axes, filtered like a click and by the open dialog's active input. Hovering a row lights it up; clicking selects it (Shift/Ctrl add) or feeds the dialog. A repeat click on the same spot with nothing changed selects the next thing there; a double-click keeps its own actions.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/ui-egui/src/lib.rs

@@ -79,6 +79,7 @@ mod revolve_edit_tests;
 #[cfg(test)]
 mod revolve_manipulator_tests;
 pub mod scenario;
+pub mod select_other;
 pub mod selection;
 #[cfg(test)]
 mod shell_face_sketch_ui_tests;