Threshold ECDSA: Building CGGMP from scratch

A step-by-step build of CGGMP, an n-of-n threshold ECDSA scheme where parties jointly produce a signature without ever reconstructing the private key. We start from the multiplicative-to-additive (MtA) protocol and a semi-honest version of the signing protocol, then harden it into a maliciously secure one by layering in zero-knowledge proofs at each step. Along the way we cover the auxiliary Ring-Pedersen and Paillier parameters and the proofs that make them safe to use.