Match the nodes in sfnetwork structure with boundary points of input lines

[agila5]

Hi everyone! I just wanted to share this SO question: https://stackoverflow.com/questions/68905319/creating-a-inla-graph-object-with-correct-index-labels-from-sf-linestring-object/68923617?noredirect=1#comment121809824_68923617

In my opinion, it presents an interesting challenge: match the nodes automatically defined by as_sfnetwork with the boundary points of the input LINESTRING(s) and extract their characteristics (the ID(s) in that case). The problem is that the structure adopted by sfnetwork does not necessarily match the order of the boundary points for the input lines.

Please let me know if there is a better approach than the one presented in that answer.