Product-Bernoulli Hypercubes: A Unified Algebra for Meji, 64-State, and Odu-256 Routing

The Hyp(d) product-Bernoulli hypercube family unifies the 16-Meji, 64-state, and Odu-256 spaces as one object at three sizes. This revision adds a Reference Implementation & Verification note to Data Availability: the paper's falsifiable claims are now numerically verified in the open-source harmonic-engine package (tests/test_new_math.py, passing on CPU). Corollaries C1 (losslessness=rank-1), C2 (factorized alignment scalars), and C4 (closed-form product Fisher–Rao) are verified for d=4,6,8 in harmonic_engine/hypercube.py and geometry.py; inline math has been re-typeset from code spans into proper math mode.