fix(statusbar): open the layout context menu at the clicked tab

The right-click menu was pinned to the screen's bottom-left corner.
Each layout tab now records its screen bounds through a PosReport
wrapper (which learned runtime-built ids for the dynamic tab names),
and the menu anchors next to the clicked tab via the shared
status-bar popup positioning, falling back to the left edge only when
no bounds were recorded (#428).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/app/view/mod.rs

@@ -1505,7 +1505,7 @@ impl OpenCADStudio {
             .unwrap_or_else(|| iced::widget::Space::new().width(0).height(0).into());
 
         let layout_ctx_layer: Element<'_, Message> = if let Some(name) = &self.layout_context_menu {
-            layout_context_menu_overlay(name)
+            layout_context_menu_overlay(name, win)
         } else {
             iced::widget::Space::new().width(0).height(0).into()
         };