Orgchain v1.6.1: under Last act, a timed beat goes to whoever acted last

A timed or manual beat used to pay the holding being worked in. Now it pays
the holding behind the newest cued act or send; with nothing cued, Beat now
still pays the one being worked in. At a timed tempo, holdings race for it.

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

README.md

@@ -14,8 +14,9 @@ chain itself records who did what, and when.
   stood at any beat.
 - **Money.** Test BTC lives at each node's SegWit address. **Mining** is a lab setting: under *Split* (the default)
   every active holding mines, and each beat's 50 test BTC splits pro rata by hashrate, a dial from 0 to 9 on each
-  holding (1 unless set), one coinbase output per holding; under *Last act* the holding that acts takes the whole
-  beat, and *Beat now* pays the one being worked in. **Send** moves test BTC from any active node to any other, in
+  holding (1 unless set), one coinbase output per holding; under *Last act* the holding behind the latest act or send
+  takes the whole beat (with nothing cued, *Beat now* pays the one being worked in), so at a timed tempo acts race
+  for the next beat. **Send** moves test BTC from any active node to any other, in
   its holding or another, signed by the sender's BIP-84 key: at most two coins in, at most 50 test BTC out, and the
   toy chain's fixed 500-sat fee. Sends land like acts, at once or cued, and *Beat now* mines a beat even when nothing
   is cued. A graduation moves each re-keyed node's money to its new address along with its inscription. Balances