feat(opcua): surgical RemoveAlarmConditionNode (R2-07 T9)

archreview/plans/R2-07-surgical-pure-adds-plan.md.tasks.json

@@ -79,7 +79,7 @@
     {
       "id": "T9",
       "subject": "Phase 2: OtOpcUaNodeManager.RemoveAlarmConditionNode (+ native-flag cleanup) (high-risk)",
-      "status": "pending",
+      "status": "completed",
       "blockedBy": [
         "T7"
       ]

src/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer/OtOpcUaNodeManager.cs

@@ -1823,7 +1823,28 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2
     }
 
     /// <inheritdoc cref="ISurgicalAddressSpaceSink.RemoveAlarmConditionNode"/>
-    public bool RemoveAlarmConditionNode(string alarmNodeId) => false;
+    public bool RemoveAlarmConditionNode(string alarmNodeId)
+    {
+        ArgumentException.ThrowIfNullOrEmpty(alarmNodeId);
+        EnsureAddressSpaceCreated();
+
+        GeneralModelChangeEventState e;
+        lock (Lock)
+        {
+            // Unknown id ⇒ map drift ⇒ false (caller rebuilds). Mirrors the condition teardown inside
+            // RebuildAddressSpace, scoped to this one condition. The equipment folder's event-notifier
+            // promotion is intentionally NOT demoted here — other conditions may still hang under it, and a
+            // lingering notifier folder is harmless (RemoveEquipmentSubtree demotes it when the whole
+            // equipment goes).
+            if (!_alarmConditions.TryRemove(alarmNodeId, out var condition)) return false;
+            condition.Parent?.RemoveChild(condition);
+            PredefinedNodes?.Remove(condition.NodeId);
+            _nativeAlarmNodeIds.Remove(alarmNodeId);
+            e = BuildNodesRemovedModelChange(alarmNodeId);
+        }
+        ReportModelChangeOutsideLock(e, alarmNodeId);
+        return true;
+    }
 
     /// <inheritdoc cref="ISurgicalAddressSpaceSink.RemoveEquipmentSubtree"/>
     public bool RemoveEquipmentSubtree(string equipmentNodeId) => false;