Proofs/DecompressSpec.lean, the arithmetic ingredients of sqrt_ratio_i:
- pow_p58_spec: a^((p-5)/8) = a^(2^252 - 3) via the pow22501 chain (the
invert_spec pattern).
- fe_ct_eq_spec: the constant-time field comparison DECIDES denotational
equality - because to_bytes is canonical (to_bytes_spec), byte equality
is residue equality in both directions. Supporting bridge lemmas:
bytesVal_inj (little-endian digits are unique, so value equality forces
list equality), bytesVal_congr, bytes_eq_iff_denote.
- sqrt(-1) needs no new work: ConstSpecs.sqrt_m1_spec (the constants
campaign) already pins SQRT_M1 to Bnd + denote*denote = -1.
Both new certificates exact standard three; full button green fresh.
Remaining in the chain: the sqrt_ratio_i success-case walk, from_bytes,
decompress_of_canonical.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
