Reject stale navigation envelopes before shared boundaries

crates/oa-desktop/src/app/allocation_drag_tests.rs

@@ -8,6 +8,8 @@ use iced::{
 #[path = "allocation_drag_full_tree_tests.rs"]
 mod full_tree;
 
+mod navigation_union;
+
 struct Fixture {
     app: App,
     a: Id,
@@ -61,6 +63,7 @@ fn canvas(app: &App) -> DiagramCanvas<'_> {
         view_index: Some(app.document.view_index()),
         diagram: app.active_diagram.unwrap(),
         selected: app.selected,
+        navigation_focus: None,
         zoom: app.zoom,
         pan: app.pan,
         context: app.route_context().unwrap(),