Cutoff for bounded product-weight random transpositions — 1.0.0-candidate

Unrefereed product-weight proof candidate. Five internal editorial roles recommend Accept; finite diagnostics are not an all-n certificate, independent reproduction, formal verification or priority clearance. DOI: 10.5281/zenodo.22662125. PDF, source ZIP and SHA256SUMS supplied; normal/optimized Linux CI passed on Python 3.10, 3.12 and 3.14.