Introduces missing CLSAG checks. The only difference now should be the
additional rejection of torsioned points, which is relevant to
https://github.com/serai-dex/serai/issues/25. Considering this is only
currently used for FROST verification, this should be fine.
Closes https://github.com/serai-dex/serai/issues/19 by making it
irrelevant.
Increases priority of https://github.com/serai-dex/serai/issues/68, as
now it's used for the BP generators which are done at first-proof.
Also merges BP's stricter hash_to_point with the library's, since CLSAG
has the same bound.
Doesn't fully utilize ec's hash2curve module as k256 Scalar doesn't have
FromOkm for some reason. The previously present bigint reduction is
preserved.
Updates ff/group to 0.12.
Premised on https://github.com/cfrg/draft-irtf-cfrg-frost/pull/205 being
merged, as while this Ed25519 is vector compliant, it's technically not
spec compliant due to that conflict.
