fix(audit): robust central options binding + interval clamps + doc/contract fixes (review)

src/ZB.MOM.WW.ScadaBridge.AuditLog/Central/SiteAuditReconciliationActor.cs

@@ -182,6 +182,10 @@ public class SiteAuditReconciliationActor : ReceiveActor
         IReadOnlyList<SiteEntry> sites;
         try
         {
+            // No ambient CancellationToken in a ReceiveActor message handler —
+            // CancellationToken.None (the EnumerateAsync default) is intentional.
+            // The work is bounded by the 5-min reconciliation tick plus the
+            // 10s graceful-stop drain on PhaseClusterLeave.
             sites = await _sites.EnumerateAsync().ConfigureAwait(false);
         }
         catch (Exception ex)