GrpcSecretSyncService's background sweep now records outcomes on a new
SecretsHubSyncStatus (registered singleton, exposed as public
ISecretsHubSyncStatus) and logs three new events on the outcome-recording
path: EventId 4 (Debug, every in-sync sweep), EventId 5 (Information, the
same outcome throttled to at most once per the new
SecretsGrpcHubClientOptions.InSyncLogInterval, default 1h), and EventId 6
(Information, the first sweep to succeed after one or more failures).
EventIds 1-3 are unchanged; the raw internal SweepAsync still throws on
failure exactly as before. Not yet published to the Gitea feed and
ScadaBridge is not re-pinned — that is a separate, later step.
Joseph Doherty