Assembler::distance(p) and stream_distance fold the brush stream into a
scalar field (Add=min, Subtract=max(d,-b), Intersect=max). Exact for boxes,
oriented boxes and Z cylinders; surface-exact non-overestimating bounds for
domes and floret arms. Honours every op on every primitive, unlike the
polygon kernel's non-box cutter warnings. Seam for isosurface meshing.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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