2 commits, squashed; the originals stay reachable from tag archive/merge-main-develop. -f042d2073jyviko: Isocurve test: the spline face's hole is an inner loop of one face (Refs #770) -cb8712aa0jyviko: Continuity: one table of orders G0-G4, and one check of what each construction builds Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01DtL5M41G8Nua7HvuFPZkmJ