Blender Git Loki

Fix T86073 : Ctrl clicking 3 times without selecting any of the verts in NurbsPath leads crash.

Crash occurs at `assert(builder->index_len < builder->max_index_len)`.

Non-bezier nurbs were being created with abnormal values causing the
causing edge count in the draw manager to be incorrect.

This commit also deduplicates and adds descriptions to the code.

Thanks @PratikPB2123 for pointing out where the error is.