Exercises the real hardware AS-build path: builds and refits triangle
and procedural BLASes with fast-build/fast-trace + allow-update flags
via one-time command buffers, asserting the requested flags land, that
an allowUpdate refit keeps the same AS handle/blasAddr (in-place
UPDATE), that the no-update / topology-change fallback still produces a
valid BLAS, and that the validation layer reports zero errors.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>