Gets the segment index of the segment containing the nearest point. The segment index is relative to the part index. For example, if PartIndex = 2 and SegmentIndex = 0, it means segment 0 in part 2. Only relevant if calling
GeometryEngine.NearestPoint, otherwise segment index is null.
Target Platforms: Windows 11, Windows 10
ArcGIS Pro version: 3 or higher.