OptionalClearOptionalIntervalOptionalLogSink for the report line.
OptionalNowClock, injectable for tests.
OptionalSetTimer factory, injectable for tests. Must return something Clear accepts.
OptionalStaleHow long an entry may sit in flight before it is treated as abandoned. <= 0 disables
eviction. See DEFAULT_STALE_AFTER_MS for why one exists at all.
Report interval.
<= 0disables reporting entirely (tracking still works).