feat(otopcua): applier pass to materialise discovered nodes idempotently

tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/OpcUa/OpcUaPublishActorRebuildTests.cs

@@ -361,6 +361,9 @@ public sealed class OpcUaPublishActorRebuildTests : RuntimeActorTestBase
             => Calls.Enqueue($"EV:{variableNodeId}");
         /// <summary>Records a rebuild address space call.</summary>
         public void RebuildAddressSpace() => Interlocked.Increment(ref RebuildCalls);
+        /// <summary>Records a NodeAdded model-change announcement.</summary>
+        /// <param name="affectedNodeId">The node under which discovered nodes were added.</param>
+        public void RaiseNodesAddedModelChange(string affectedNodeId) => Calls.Enqueue($"NA:{affectedNodeId}");
         /// <summary>Records a surgical in-place tag-attribute update (always succeeds in this recording sink).</summary>
         public bool UpdateTagAttributes(string variableNodeId, bool writable, string? historianTagname, string dataType, bool isArray, uint? arrayLength)
         {

tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/OpcUa/OpcUaPublishActorTests.cs

@@ -596,6 +596,10 @@ public sealed class OpcUaPublishActorTests : RuntimeActorTestBase
 
         /// <summary>Records a rebuild call.</summary>
         public void RebuildAddressSpace() => Interlocked.Increment(ref RebuildCalls);
+
+        /// <summary>Announces a NodeAdded model-change (no-op in test).</summary>
+        /// <param name="affectedNodeId">The node under which discovered nodes were added.</param>
+        public void RaiseNodesAddedModelChange(string affectedNodeId) { }
     }
 
     /// <summary>Test implementation of IServiceLevelPublisher that records publishes.</summary>