Dragging to reorder

Unity's animated dragger does take pointer events sent through a panel, so the ui_toolkit_list_drag scenario records it: canStartDrag on the press (its id, selected ids and the item's root), the drag starting past 10 pixels (9 doesn't, 13 does); animated lists clear and set the selection again, lift the item (absolute, at its place; brought to the front on the next move, then following the pointer from there, never above the top), keep its place with an empty item and give the item below room (padding and height); the drop moves it to the slot under its top, selecting it without an event, and the rows show the new order at once.
Simple lists: setupDragAndDrop when the drag starts (the item's text as the title, Move), the title in a label by the pointer on the panel's root. Unity's runtime drag and drop finishes only through its own events, so the drop marker and the drop aren't compared: Tassix shows the marker between items (styled with the theme's accent) and drops there, asking dragAndDropUpdate and handleDrop; an e2e test drives them.
The drag-and-drop API: CanStartDragArgs, SetupDragAndDropArgs, StartDragArgs, HandleDragAndDropArgs, DragAndDropData, IDragAndDropData, DragVisualMode, DragAndDropPosition, and the four events.
Collection items keep their side margins and lose only the top and bottom ones and the top padding, as Unity's theme does (label items).
Not yet: entity ids in drag data (Tassix has no EntityId), dragging between views, auto-scrolling while dragging.
Next: whatever the corpus asks for next; the remaining custom shader gaps (point and spot lights, shadows, GrabPass).