Extraction widened to backend::serial::curve_models + edwards (v4 Aeneas).
Ed* proof suite shared with the risc0 twin EXCEPT proj_double_spec: upstream
reordered ProjectivePoint::double's instructions between v4.1.2 (this fork)
and v4.1.3 (risc0), so the step sequence was resequenced to match THIS
fork's generated body — the proofs track each fork's actual code, not a
template. All 20 proofs pass under lean-guard; both certificates axiom-clean.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
