Terminology confusion regarding LegoSNARK

The diff reviewed for this audit introduced support for the variant of Groth16 proofs emitted by gnark (with some restrictions on the number of commitments and that commitments must be for nonpublic witnesses).

The specification describes this variant of Groth16 as LegoSNARK's "commit-and-prove" extension, as defined in the LegoSNARK paper↗ by Matteo Campanelli, Dario Fiore, and Anaïs Querol. However, this is not accurate. Instead, gnark's variant is custom and more closely related to the paper Recursion Over Public-Coin Interactive Proof Systems; Faster Hash Verification↗ by Alexandre Belling, Azam Soleimanian, and Olivier Bégassat. While all three schemes involve commitments to witnesses, there are also a number of differences.