Defers LayerManager, desktop panel activation, Scale and CoordinatesDisplay to
the geoleaf:app:ready event. (Legend now mounts via LegendLifecycle; the
label system via LabelsLifecycle during registry.init().)
The teardown UIModule.destroy() runs when the application is unmounted: an
application gone before its reveal must not build its panels on the next one's.
Defers LayerManager, desktop panel activation, Scale and CoordinatesDisplay to the
geoleaf:app:readyevent. (Legend now mounts viaLegendLifecycle; the label system viaLabelsLifecycleduringregistry.init().)