This is version 4.2 – the cleaned and refined version (13 pages) with removed speculative sections, consistent propagator derivation, bimetric origin, quantitative void horizon properties (blueshift + memory time), updated fσ₈ plot with DESI/BOSS points, and Boltzmann roadmap for future MCMC analysis. Previous intermediate versions are available as separate records or in version history.
Hruznov et al. (Mon,) studied this question.