feat(sitecallaudit): central→site Retry/Discard relay for parked operations

src/ScadaLink.Communication/Actors/SiteCommunicationActor.cs

@@ -167,6 +167,33 @@ public class SiteCommunicationActor : ReceiveActor, IWithTimers
             }
         });
 
+        // Task 5 (#22): central→site Retry/Discard relay for parked cached
+        // operations. SiteCallAuditActor relays these over the command/control
+        // channel; the parked-message handler executes them against the local
+        // S&F buffer and replies a ParkedOperationActionAck that routes back to
+        // the relaying SiteCallAuditActor's Ask.
+        Receive<RetryParkedOperation>(msg =>
+        {
+            if (_parkedMessageHandler != null)
+                _parkedMessageHandler.Forward(msg);
+            else
+            {
+                Sender.Tell(new ParkedOperationActionAck(
+                    msg.CorrelationId, Applied: false, "Parked message handler not available"));
+            }
+        });
+
+        Receive<DiscardParkedOperation>(msg =>
+        {
+            if (_parkedMessageHandler != null)
+                _parkedMessageHandler.Forward(msg);
+            else
+            {
+                Sender.Tell(new ParkedOperationActionAck(
+                    msg.CorrelationId, Applied: false, "Parked message handler not available"));
+            }
+        });
+
         // Notification Outbox: forward a buffered notification submitted by the site
         // Store-and-Forward Engine to the central cluster. The original Sender (the
         // S&F forwarder's Ask) is forwarded as the ClusterClient.Send sender so the