Never let a pending horde pour onto a boss stage

Game 30 is both a set and the third chapter boss. pendingHorde is a LATCH: the
set arms it and the next 'over' beat to expire cashes it — and with the boss
outranking the set at that clear, the next beat to expire was the chapter card.
The wave arrived on top of the boss.

The latch is now left alone while a boss fight or a duel is running, so the beat
after the fight cashes it: the set still gets its horde, just not on top of the
thing that outranked it. Verified both halves — ten seconds of boss fight with
the latch armed and no spawn, then the wave arriving once the boss is down.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

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