refactor(opcua): repoint Phase7Applier + VirtualTagHostActor to shared EquipmentNodeIds

src/Server/ZB.MOM.WW.OtOpcUa.Runtime/VirtualTags/VirtualTagHostActor.cs

@@ -17,10 +17,9 @@ namespace ZB.MOM.WW.OtOpcUa.Runtime.VirtualTags;
 ///     already-materialised Variable node (currently BadWaitingForInitialData) reflects the value.
 ///
 ///     <para>
-///         The published NodeId is computed with the <b>identical</b> formula
-///         <c>Phase7Applier.MaterialiseEquipmentVirtualTags</c> uses to materialise the variable —
-///         <c>{parent}/{Name}</c> where <c>parent = IsNullOrWhiteSpace(FolderPath) ? EquipmentId :
-///         {EquipmentId}/{FolderPath}</c> — or the value would land on a NodeId that does not exist.
+///         The published NodeId is computed by the shared <see cref="EquipmentNodeIds.Variable"/> —
+///         the single source of truth <c>Phase7Applier.MaterialiseEquipmentVirtualTags</c> also
+///         materialises against — so the value always lands on a NodeId that exists.
 ///     </para>
 /// </summary>
 public sealed class VirtualTagHostActor : ReceiveActor
@@ -143,14 +142,9 @@ public sealed class VirtualTagHostActor : ReceiveActor
         }
     }
 
-    /// <summary>Folder-scoped NodeId for a VirtualTag plan — MUST match
-    /// <c>Phase7Applier.MaterialiseEquipmentVirtualTags</c> exactly, or the published value lands on a
-    /// NodeId that was never materialised.</summary>
-    private static string NodeIdFor(EquipmentVirtualTagPlan p)
-    {
-        var parent = string.IsNullOrWhiteSpace(p.FolderPath)
-            ? p.EquipmentId
-            : $"{p.EquipmentId}/{p.FolderPath}";
-        return $"{parent}/{p.Name}";
-    }
+    /// <summary>Folder-scoped NodeId for a VirtualTag plan. The formula now lives in the shared
+    /// <see cref="EquipmentNodeIds"/> (the single source of truth that <c>Phase7Applier</c> also
+    /// materialises against), so the published value always lands on the NodeId that was materialised.</summary>
+    private static string NodeIdFor(EquipmentVirtualTagPlan p) =>
+        EquipmentNodeIds.Variable(p.EquipmentId, p.FolderPath, p.Name);
 }