Pull Request Overview

This PR migrates the Binary Merkle Tree (BMT) proof serialization to use the commonware_codec traits instead of custom methods, and updates fuzz targets accordingly.

• Implement Write, Read, and EncodeSize for Proof<H> and remove old serialize/deserialize methods
• Introduce a MAX_SIBLINGS bound and switch tests/fuzz targets to encode/decode
• Add commonware-codec as a dependency in the fuzz workspace

Reviewed Changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 3 comments.

#[test]
fn decode_too_many_siblings() {
    let mut serialized = Vec::new();
    // write length prefix > MAX_SIBLINGS
    serialized.extend(((MAX_SIBLINGS + 1) as u64).encode());
    serialized.extend(vec![0u8; (MAX_SIBLINGS + 1) * Sha256::Digest::SIZE]);
    let mut buf = serialized.as_slice();
    assert!(Proof::<Sha256>::decode(&mut buf).is_err());
}

    #[test]

//! assert!(proof.verify(&mut hasher, &digests[1], 1, &root).is_ok());