Interface IDragHorizontalTentative
A horizontal-axis drag that is willing to yield capture to a vertical-axis ancestor whose drag intent appears stronger. Used by horizontal scroll views nested inside vertical ones: the inner scrolls horizontally from the first pointer move, but if the user's motion is dominantly vertical when crossing the recognition threshold, the outer scroll view steals capture.
The capturing view is expected to "promote" itself by re-capturing with a plain IDrag (e.g. Drag) once horizontal motion has clearly committed to its axis (typical threshold: 20pt of horizontal travel). After promotion, vertical ancestors can no longer steal capture for this pointer.
public interface IDragHorizontalTentative : IDrag, IPointerGesture