The host does not guarantee IHostedService.StopAsync is driven before the DI
container is disposed — WebApplicationFactory's teardown reaches Dispose first
— so cancelling the internal CTS from StopAsync threw ObjectDisposedException
and aborted the host's whole shutdown sequence. Four services shared the same
copy-pasted lifecycle and the same two races: StopAsync cancelling an already-
disposed CTS, and StartAsync reading _cts.Token lazily inside the Task.Run
lambda, which faults the loop task the host awaits when Dispose wins that race.
Each service now captures the token on the caller's thread, tolerates a
disposed CTS, and cancels-before-disposing so the loop is always signalled and
its pending Task.Delay sees a cancelled token rather than a dead source.
SiteAuditBacklogReporter also gains the outer OperationCanceledException guard
its sibling SiteAuditRetentionService already carried (arch-review 04 R2, R7),
without which a shutdown landing mid-probe threw TaskCanceledException out of
Host.StopAsync.
Surfaced while verifying the Gitea #15 test-harness fix: in Host.Tests the
aborted teardown skipped the fixture's env-var restore, contaminating every
later test in the run.
Refs: Gitea #15
SiteAuditRetentionService (site-only IHostedService) ticks PurgeExpiredAsync on
InitialDelay(5m)/PurgeInterval(24h, clamped >=1m), cutoff = UtcNow - RetentionDays.
Registered site-only in AddAuditLogHealthMetricsBridge; options bound from
AuditLog:SiteRetention. Per-tick failures swallowed. Added a test-only
PurgeIntervalOverride (mirrors SiteCallAuditOptions) so the ms-cadence tick test
can bypass the 1-min production clamp. Doc updated. (PLAN-04 Task 3, S1/U2)
Joseph Doherty