Add ISM as a drop-in replacement for ESM2

https://huggingface.co/jozhang97/ism_t33_650M_uc30pdb

https://www.biorxiv.org/content/10.1101/2024.11.08.622579v1

https://github.com/jozhang97/ISM

Should better capture structural semantics in the latent embeddings. Would need to be benchmarked, but very easy to implement.