fix(siteruntime): normalize routed WaitForAttribute response value for cross-process transport

src/ZB.MOM.WW.ScadaBridge.SiteRuntime/Actors/DeploymentManagerActor.cs

@@ -1108,8 +1108,19 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
         // Ask bounded by the WAIT timeout + slack — NOT a fixed 30s (the wait legitimately blocks up to request.Timeout).
         instanceActor.Ask<WaitForAttributeResponse>(inner, request.Timeout + TimeSpan.FromSeconds(5))
             .ContinueWith(t => t.IsCompletedSuccessfully
+                // The matched value crosses the Central↔Site PROCESS boundary inside this
+                // response. For a List-typed attribute the Instance Actor's matched
+                // `WaitForAttributeResponse.Value` is a concrete generic List<T>
+                // (List<int>/List<double>/List<DateTime>/… built by TryCoerceListValue;
+                // see InstanceActor.HandleTagValueUpdate / ResolveMatchedWaiters) — a
+                // non-primitive shape that Akka's cross-process serializer cannot reliably
+                // round-trip, which would silently drop the reply and hang the caller's
+                // Ask. Project it through the same normalizer RouteInboundApiCall uses so
+                // the wire carries a plain CLR graph (List/primitive). Scalars/strings/null
+                // pass through unchanged.
                 ? new RouteToWaitForAttributeResponse(
-                    request.CorrelationId, t.Result.Matched, t.Result.Value, t.Result.Quality, t.Result.TimedOut,
+                    request.CorrelationId, t.Result.Matched, NormalizeRoutedReturnValue(t.Result.Value),
+                    t.Result.Quality, t.Result.TimedOut,
                     true, null, DateTimeOffset.UtcNow)
                 : new RouteToWaitForAttributeResponse(
                     request.CorrelationId, false, null, null, false,