Module extent 

Canonical pack-extent claims — the physical half of the reshape’s read path.

A manifest node names only immutable logical facts. Where an object’s bytes actually live is a mutable control-plane fact, so it never enters the content root; repacking must change a read envelope, not a manifest hash. This module gives that envelope a canonical encoding of its own so it can be signed, transported, and checked byte-for-byte.

Two rules from the downstream consumer are load-bearing and reproduced here exactly:

• Offset-canonical ordering. Records are ordered by pack offset, not by object key. Packs are laid out for delta compression, so object order and physical order routinely disagree; ordering by object first makes valid coalesced ranges fail their contiguity check (weft #1070, the bug fixed after weft #1069 merged).
• Gap-free coverage. A coalesced range carries a sorted partition of its authorized records that covers [start, end) exactly — no gap, no overlap. A pack may hold objects of mixed audience, so one physical range read must never authorize an unselected byte gap between two authorized records. Coalescing joins exactly adjacent extents only.

claim: "WPMX" | u8(version=1) | u16(pack_id_len) | pack_id
              | u16(etag_len) | etag | u64(start) | u64(end)
              | u32(record_count)
              | count * ( u8(kind) | [u8;32](object_hash)
                        | u64(decoded_size) | u64(offset) | u64(length)
                        | [u8;32](encoded_digest) )

Structs

PackRangeClaim

One coalesced physical range read, plus the partition of authorized records it covers.

PackRecord

One object’s physical slice of a pack.

Enums

PackClaimDecodeError

Constants

PACK_CLAIM_MAGIC

Magic prefix on every canonical pack-range claim.

PACK_CLAIM_VERSION

The only claim format version this binary reads or writes.