spatial.rs in solvecraft-cli: read binary or ASCII STL; bounds, volume, centre of mass and principal second moments of a closed triangle mesh (signed tetrahedra, Jacobi eigenvalues); sampled symmetric Hausdorff distance between two meshes using a uniform grid with an expanding-shell search. Unit test on a cube (moments and a 0.3 mm offset). Not called from CLI commands yet. Co-Authored-By: Claude Opus 5.5 <[email protected]>