Orgchain v1.7: items, standing offers and the first deal; a Mainnet setting

The chain takes ordinary spends of up to eight inputs and outputs, whose
key-path signatures may carry SIGHASH_SINGLE|ANYONECANPAY (0x83); reveals
keep their two-in, two-out shape. A new make op records an item, an
inscription its maker holds. Any node can offer test BTC for an item another
node holds, in any holding: the buyer's SegWit key signs the whole deal, the
offer stands in the lab, and the holder accepts by countersigning the item's
input, so the item and the payment swap in one transaction. Offers go stale
when a promised coin moves or a side re-keys or closes, and payments spend
unpromised coins first. Sends take up to eight coins. Mainnet is a third
mining setting: no holding mines, beats pay the lab wallet, and holdings are
funded from it. The sample ends on lineage's open offer for sol's launch-kit.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01H4upF5LVwmPDDqrhdUfnXh

PROVENANCE.md

@@ -20,7 +20,7 @@ Runtime dependencies are pinned in `package.json` and `package-lock.json`:
 - **@scure/bip32 1.7.0**, Patricio Palladino and Paul Miller, [upstream](https://github.com/paulmillr/scure-bip32), MIT. Used for HD derivation under the BIP-85, BIP-86, BIP-84 and NIP-06 paths. License retained at [`public/licenses/scure-bip32.txt`](public/licenses/scure-bip32.txt).
 - **@scure/bip39 1.6.0**, Patricio Palladino and Paul Miller, [upstream](https://github.com/paulmillr/scure-bip39), MIT. Used for the 24-word lab roots and their seeds. License retained at [`public/licenses/scure-bip39.txt`](public/licenses/scure-bip39.txt).
 
-Two local changes to the engine, both original code in `src/adapters/chain.js`, tested in `tests/money.test.js`, with Super Testnet's tests (`tests/adapters.test.js`) passing unchanged. Orgchain v1.5: the chain also accepts native SegWit (P2WPKH) outputs and SIGHASH_ALL P2WPKH spends, verified per BIP-143, so lineage accounts can hold and send test BTC at their BIP-84 addresses; everything about inscriptions stays Taproot-only. Orgchain v1.6: a coinbase may split the block reward across up to 64 outputs (`mineTo`; `mine` still pays one script), so one beat can pay several holdings.
+Three local changes to the engine, all original code in `src/adapters/chain.js`, tested in `tests/money.test.js`, with Super Testnet's tests (`tests/adapters.test.js`) passing unchanged. Orgchain v1.5: the chain also accepts native SegWit (P2WPKH) outputs and SIGHASH_ALL P2WPKH spends, verified per BIP-143, so lineage accounts can hold and send test BTC at their BIP-84 addresses; everything about inscriptions stays Taproot-only. Orgchain v1.6: a coinbase may split the block reward across up to 64 outputs (`mineTo`; `mine` still pays one script), so one beat can pay several holdings. Orgchain v1.7: ordinary (non-reveal) spends may take up to eight inputs and outputs (`MAX_IO`), and their key-path Taproot signatures may carry SIGHASH_SINGLE|ANYONECANPAY (0x83, the sell-order flag), so one transaction can carry a deal: an item, the buyer's coins, the price and change. Reveals keep their two-in, two-out shape and default signatures.
 
 Vite and Playwright are build/test dependencies, not runtime network services. Their installed package notices remain in the locked dependency installation. No unlicensed upstream code was copied.