The geometry information at the selection end.
This information is used for drawing mobile selection controls. The SelectionPoint.localPosition of the selection end is typically at the end of the selection highlight at where the end selection handle should be drawn.
The SelectionPoint.handleType should be TextSelectionHandleType.right for forward selection or TextSelectionHandleType.left for backward selection in most cases.
Can be null if the selection end is offstage, for example, when the selection is outside of the viewport or is kept alive by a scrollable.
final SelectionPoint? endSelectionPoint;