Gravity, Horizons, and Black Holes in the Finite-QEC Substrate

States the gravity and horizon canon of the finite-QEC substrate program: the proton-primary route in which the measured proton mass fixes the chiral scale and the accounting chain predicts G, the Planck mass, and H0 = 67.27 km/s/Mpc; the Bekenstein severing-channel count C = 55/8 and its alpha-free image OmegaLambda = 12π/55; a finite-cell horizon isometry, a Schwarzschild shell channel, and a finite Hawking ladder on the 208-state invalid subspace; and explicit falsification surfaces — a 22-ppm CODATA test of G once the alpha-convention gate resolves, and death of the H0 prediction under a SH0ES-side resolution of the Hubble tension. Copyright (C) 2026 D. G. Elliman. Version 2.0 (2026-06-15). Added a gravitational-wave channels section: the Einstein field form Gμν=8πG Tμν is intrinsic (entanglement thermodynamics, Jacobson δQ=TδS; emergent MPl≈1.7 GeV at the lattice scale); a pulsar-timing-band stochastic background (sub-threshold, T*∼ΛQCD); and ringdown echoes (Δt≈56 ms at 30 M⊙, reflectivity R≈1, spacing set by a₀=1/ΛQCD) as a LIGO/LISA test. Version 2.1 (2026-06-15). Echo correction: the v2.0 near-unit ringdown-echo (R~1) reading is WITHDRAWN. The QEC horizon is a one-way record-writing channel, not a coherent mirror, so the canonical prediction is a LARGE-ECHO NULL; LIGO/LISA echo searches are upper-bound tests on extra horizon structure, not a positive prediction. The PTA stochastic-background and intrinsic-Einstein-form additions are unchanged.