feat(sitecall-audit): add SourceNode to SiteCallOperational + SiteCall entity

tests/ScadaLink.Commons.Tests/Types/SiteCallOperationalTests.cs

@@ -0,0 +1,42 @@
+using ScadaLink.Commons.Types;
+
+namespace ScadaLink.Commons.Tests.Types;
+
+/// <summary>
+/// Verifies <see cref="SiteCallOperational"/> — the positional record carried on
+/// the combined <c>CachedCallTelemetry</c> packet — round-trips the SourceNode
+/// field through positional construction (where the parameter sits between
+/// <c>SourceSite</c> and <c>Status</c>, mirroring the central <c>SiteCalls</c>
+/// table column order).
+/// </summary>
+public class SiteCallOperationalTests
+{
+    [Fact]
+    public void SiteCallOperational_carries_SourceNode()
+    {
+        // SourceNode identifies the cluster node that emitted the cached call
+        // (site node-a/node-b or central-a/central-b). Nullable — callsites
+        // pass null until INodeIdentityProvider stamping arrives in Task 14.
+        var trackedId = TrackedOperationId.New();
+        var nowUtc = new DateTime(2026, 5, 23, 12, 0, 0, DateTimeKind.Utc);
+
+        var defaulted = new SiteCallOperational(
+            TrackedOperationId: trackedId,
+            Channel: "ApiOutbound",
+            Target: "ERP.GetOrder",
+            SourceSite: "site-01",
+            SourceNode: null,
+            Status: "Submitted",
+            RetryCount: 0,
+            LastError: null,
+            HttpStatus: null,
+            CreatedAtUtc: nowUtc,
+            UpdatedAtUtc: nowUtc,
+            TerminalAtUtc: null);
+        Assert.Null(defaulted.SourceNode);
+
+        var stamped = defaulted with { SourceNode = "node-a" };
+        Assert.Equal("node-a", stamped.SourceNode);
+        Assert.Null(defaulted.SourceNode);
+    }
+}