Pinch cause: SmoothStep taper drove the underside radius to zero at one point. Version 2: depth 0.75x
diameter (thin-pad control at 0.30 fails), 3-4 seeded roots, bounded contour warp + roughness, one
off-route side island, 3 m rock spans. Bounds/route/W1-W8-W16 pass. Open: legacy probe metadata says
25 cm but production legacy is 12.5 cm -- round 3 must fix the import scale contract.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ