forked from 1b-agent/fieldcraft-upstream
The face's triangles are cut along the plane, split:<name>:a on its negative side and :b on the other, both on the face's surface, with the cut as a new edge between them and the face's edges cut where the plane crosses them. Applied after the merges; the B-rep is unchanged. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo