fix(site-runtime): resolve SiteRuntime-001/002/003 — route data-sourced writes to DCL, real per-attribute API results, race-free redeploy

tests/ScadaLink.SiteRuntime.Tests/Actors/InstanceActorIntegrationTests.cs

@@ -123,9 +123,12 @@ public class InstanceActorIntegrationTests : TestKit, IDisposable
                 $"corr-{i}", "Pump1", "Temperature", $"{i}", DateTimeOffset.UtcNow));
         }
 
-        // SetStaticAttributeCommand is fire-and-forget; the GetAttributeRequest
-        // round-trip below is the sync point — the FIFO mailbox guarantees all
-        // 50 sets are processed before the get is.
+        // Each static write replies with a SetStaticAttributeResponse; drain all
+        // 50 — the FIFO mailbox guarantees they are processed in order.
+        for (int i = 0; i < 50; i++)
+        {
+            ExpectMsg<SetStaticAttributeResponse>(TimeSpan.FromSeconds(5));
+        }
 
         // The last value should be the final one
         actor.Tell(new GetAttributeRequest(