Release counter-sign 0.1.2 · countersign-labs/counter-sign

counter-sign 0.1.2

Makes the ReceiptLog approval history tamper-evident for completeness, not just per-receipt authenticity.

Hash-chained log — each entry commits to a SHA-256 of the entry before it, so an edit, reorder, insertion, or mid-stream deletion breaks the chain and is detectable offline. verifyChain() names the first break; verifyAll() now folds the chain into ok (true only when every receipt is genuine and the chain is intact).
head() + expectedHead — checkpoint the chain head and anchor it externally to catch tail truncation, the one thing a forward chain can't detect on its own.
New types: ChainEntry, ChainHead, ChainReport.

On-disk log line is now a chained envelope { seq, prev, receipt } instead of a bare receipt. Pre-0.1.2 logs still read (flagged as unchained-entry by verifyChain). No change to the protocol or the Countersignature wire format — receipts inside are byte-for-byte the same portable artifact.