may be possible to use use std::execution::par

[CEXT-Dan]

Hi,
Thanks for the routine, it's crazy fast.
I noticed line 306 can use std::execution::par for a tiny speedup

par shaved a fair amount of time off, though using par_unseq wasn't any better

// sort the points by distance from the seed triangle circumcenter
std::sort(std::execution::par,ids.begin(), ids.end(), compare{ coords, m_center_x, m_center_y });

GenTin Num Points = 1000000, time = 631.198200
GenTin Num Points = 1000000, time = 510.206700 par
GenTin Num Points = 1000000, time = 509.641300 par_unseq

cheers, can close