This issue is to track standards for persisting ML-KEM keys as well as to suggest implementing them. In terms of implementation, this issue thus suggests adding encoding/decoding logic for all ML-KEM key components.

This below is to track the standards defining these formats to enable subsequent implementation of those (draft only):

• Standard for public key format: "encapsulation key ek" binary format from FIPS203 section 6.1 and encoded as per draft specification https://datatracker.ietf.org/doc/draft-ietf-lamps-kyber-certificates/06/
• Standard for private key format: "seed"-format as per section 5 in draft specification https://datatracker.ietf.org/doc/draft-ietf-lamps-kyber-certificates/06/

Proposed target for any PRs currently is the "ml-kem" feature branch.

Input solicited, particularly from @tomato42 and @t-j-h