The grip used a bare MouseArea for the drag. Inside the ListView (a
Flickable), once the pointer moved past the drag threshold the ListView
stole the gesture for flicking, so the grip's positionChanged stopped
firing: the drop target was never resolved and release did nothing.
Replace the MouseArea with a DragHandler (target: null — it tracks, it
doesn't move the item) whose grabPermissions take the pointer grab and
refuse to yield it to the Flickable, so the drag is no longer stolen. It
reports centroid.scenePosition continuously, mapped to ListView content
coordinates via contentItem.mapFromScene, driving the same updateDrop/
commitDrop path. A HoverHandler keeps the hover affordance, and the grip
gets a slightly larger hit target.
QML compiles (AOT cache build of OutlineView). The drop resolution and
refile commit paths were already verified; this restores the gesture
that feeds them.
0a06ca60bf