verify_accepts_iff_point_eq, button-enforced
Port of dalek's PointEqSpec (the encoding-injectivity mathematics is
fork-independent; compiled first try): for any valid on-curve point Q
whose canonical encoding is the signature's R bytes, the verifier
accepts IFF Q equals the recomputed point as denoted affine points -
the literal point-level EdDSA verification equation, no decompress
needed. enc_point_inj carries the standard three axioms; the equation
itself carries exactly this fork's enforced apex boundary, and Phase 3b
now audits all three tiers (byte apex, half-lift, point equation).
Full button green fresh.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>