4 commits, squashed; the originals stay reachable from tag archive/merge-main-develop. -bf51e62f7jyviko: Kernel tests: a law's dip shows its corner ball's sphere, a peak's two rounds cross (the reasons had them swapped) -cde8be4a1jyviko: Reference tests: the variable rounds 77, 78, 80 and 81 expect the union of their balls -155f1f470jyviko: Known failing: the law corners' kernel and crate tests and rig 1207 pass on SMLib 48ea616 -21f00a917jyviko: Kernel rig: every fillet and chamfer case rounds its tangent chain Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01DtL5M41G8Nua7HvuFPZkmJ