convexHullSet
Computes the convex hull of a list of 2D points and returns the vertices of the hull as a set. The convex hull is the smallest convex polygon that can enclose all points in the input list.
This method uses the convexHull function to calculate the hull and extracts the starting points of the contour segments to represent the vertices of the hull.
Receiver
A list of 2D points represented as Vector2.
Return
A set of Vector2 representing the vertices of the computed convex hull. If the input list is empty or has fewer than three unique points, the resulting set will represent a simplified contour matching the input points.