feat(ui): add Node column + filter to NotificationOutbox grid

tests/ScadaLink.NotificationOutbox.Tests/NotificationOutboxActorQueryTests.cs

@@ -149,6 +149,45 @@ public class NotificationOutboxActorQueryTests : TestKit
             1, 50, Arg.Any<CancellationToken>());
     }
 
+    [Fact]
+    public void Query_PassesSourceNodeFilter_AndProjectsSourceNodeOntoSummary()
+    {
+        // Task 16: the Notifications page's new Node filter input pushes a
+        // value into NotificationOutboxQueryRequest.SourceNodeFilter; the actor
+        // must thread it onto NotificationOutboxFilter.SourceNode AND mirror
+        // the row's SourceNode column onto the response summaries.
+        var row = MakeNotification(status: NotificationStatus.Pending);
+        row.SourceNode = "central-a";
+        _repository.QueryAsync(
+                Arg.Any<NotificationOutboxFilter>(), Arg.Any<int>(), Arg.Any<int>(), Arg.Any<CancellationToken>())
+            .Returns(((IReadOnlyList<Notification>)new[] { row }, 1));
+        var actor = CreateActor();
+
+        actor.Tell(
+            new NotificationOutboxQueryRequest(
+                CorrelationId: "corr-node",
+                StatusFilter: null,
+                TypeFilter: null,
+                SourceSiteFilter: null,
+                ListNameFilter: null,
+                StuckOnly: false,
+                SubjectKeyword: null,
+                From: null,
+                To: null,
+                PageNumber: 1,
+                PageSize: 50,
+                SourceNodeFilter: "central-a"),
+            TestActor);
+
+        var response = ExpectMsg<NotificationOutboxQueryResponse>();
+        Assert.True(response.Success);
+        Assert.Equal("central-a", response.Notifications.Single().SourceNode);
+
+        _repository.Received(1).QueryAsync(
+            Arg.Is<NotificationOutboxFilter>(f => f.SourceNode == "central-a"),
+            1, 50, Arg.Any<CancellationToken>());
+    }
+
     [Fact]
     public void Query_RepositoryThrows_RepliesFailureWithEmptyList()
     {