Regression test for the procedural BLAS path: the same 3x3x3 grid of
unit-box AABBs runs through a PROCEDURAL_HIT_GROUP_KHR group whose GLSL
intersection shader (reportIntersectionEXT) turns each box into a
radius-1 sphere, the any-hit shader punches the spherical-checkerboard
cut-out (visible proof non-opaque geometry runs any-hit), and the
closest-hit shades per-instance tints — the WebGPU example behavior
reproduced natively. Fixed camera in raygen.glsl; the WebGPU/DOM path is
unchanged.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
