Module block 

L2Block — full L2 block: header, transaction body (SpendBundles), slash proposal payloads, proposer signature.

Requirements:

• BLK-003 — struct + new / hash / height / epoch
• HSH-003 — crate::compute_spends_root (spends Merkle root)
• HSH-004 — crate::compute_additions_root (additions Merkle set)
• HSH-005 — crate::compute_removals_root (removals Merkle set)
• HSH-006 — crate::compute_filter_hash (BIP-158; L2Block::compute_filter_hash keys SipHash with L2BlockHeader::parent_hash per SPEC §6.4)
• BLK-004 — Merkle roots, BIP158 filter_hash preimage, additions/removals collectors, duplicate / double-spend probes, serialized size
• SVL-005 — header/body count agreement (L2Block::validate_structure; SPEC §5.2 steps 2, 4, 5, 13) before expensive Merkle checks (SVL-006)
• SER-002 — L2Block::to_bytes / L2Block::from_bytes (bincode + BlockError::InvalidData on decode)
• SPEC §2.3, SPEC §3.3–§3.6 — body commitments + filter

Usage

Build a block by assembling an L2BlockHeader (commitments, roots, counts) and the body fields. Canonical identity is L2Block::hash → L2BlockHeader::hash only; spend bundles and slash bytes are committed via Merkle roots in the header, not mixed into this hash (SPEC §2.3 / BLK-003 notes).

Rationale

• SpendBundle comes from chia-protocol so CLVM spends match L1/Chia tooling (BLK-003).
• Signature is the chia-bls type re-exported as crate::primitives::Signature (BLK-006) so callers import one dig_block surface.
• slash_proposal_payloads are Vec<Vec<u8>> for opaque slash evidence (encoding evolves independently).

Structs

L2Block

Complete L2 block: header plus body (spend bundles, slash payloads) and proposer attestation.