RPM invariant now buckets by admit time on the Redis server clock,
exempts +/-2s boundary jitter, and excludes cache-hit rows that never
consumed a limiter slot. RSS sampling reports current ps RSS instead of
the monotonic ru_maxrss peak. Dispatch is paced by the concurrency
semaphore so --max-hours stays live and memory stays bounded. Add
--rescore RUN_ID to re-judge a finished run offline.
iomgaa