docs(galaxy): fix stale SystemPlatform/alias/Galaxy doc comments (review follow-up)

Resolves the code-review notes on 95be607a + the AdminUI bundle: the
EnsureVariable docs (IOpcUaAddressSpaceSink, OtOpcUaNodeManager) and the Tag
entity doc no longer say 'Galaxy / SystemPlatform / alias'; the DriverHostActor
ForwardToMux comment now states the real equipment-tag value-routing gap (the
FullName→NodeId 'live values' milestone) instead of claiming Galaxy values map
straight through.

src/Core/ZB.MOM.WW.OtOpcUa.Commons/OpcUa/IOpcUaAddressSpaceSink.cs

@@ -55,7 +55,7 @@ public interface IOpcUaAddressSpaceSink
     ///     Ensure a Variable node exists at <paramref name="variableNodeId"/>, parented under
     ///     <paramref name="parentFolderNodeId"/> (or the namespace root when null). Created with
     ///     Bad quality + null value; subsequent <see cref="WriteValue"/> calls update both.
-    ///     Used by <c>Phase7Applier</c> to materialise Galaxy / SystemPlatform tags ahead of any
+    ///     Used by <c>Phase7Applier</c> to materialise equipment-namespace tags ahead of any
     ///     driver-side subscribe so OPC UA clients can browse them. Idempotent.
     /// </summary>
     /// <param name="variableNodeId">The OPC UA node ID for the variable.</param>

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/Entities/Tag.cs

@@ -4,10 +4,9 @@ namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
 
 /// <summary>
 ///     One canonical tag (signal) in a cluster's generation. <see cref="EquipmentId"/> set ⟺ the
-///     tag participates in the Equipment tree, regardless of the driver's namespace kind. A
-///     <c>GalaxyMxGateway</c>-bound equipment tag is an <em>alias</em> — a Galaxy attribute surfaced
-///     under a UNS name, with its Galaxy reference carried in <c>TagConfig.FullName</c>.
-///     <see cref="EquipmentId"/> is NULL for SystemPlatform mirror tags (FolderPath-scoped).
+///     tag participates in the Equipment tree. A <c>GalaxyMxGateway</c>-bound equipment tag is an
+///     ordinary equipment tag (GalaxyMxGateway is a standard Equipment-kind driver) that carries its
+///     Galaxy attribute reference in <c>TagConfig.FullName</c> — there is no separate alias concept.
 /// </summary>
 public sealed class Tag
 {

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

@@ -626,8 +626,8 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2
     ///     Ensure a Variable node exists at <paramref name="variableNodeId"/> parented under
     ///     <paramref name="parentFolderNodeId"/> (or root when null). Initial value=null, quality=Bad,
     ///     timestamp=epoch — <see cref="WriteValue"/> fills these in once driver data flows.
-    ///     Idempotent. Materialises Galaxy / SystemPlatform tags so they're browseable before the
-    ///     Galaxy driver issues SubscribeBulk.
+    ///     Idempotent. Materialises equipment-namespace tags so they're browseable before drivers
+    ///     issue SubscribeBulk.
     /// </summary>
     /// <param name="variableNodeId">The node identifier of the variable.</param>
     /// <param name="parentFolderNodeId">The node identifier of the parent folder; null to use the namespace root.</param>

src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Drivers/DriverHostActor.cs

@@ -383,10 +383,12 @@ public sealed class DriverHostActor : ReceiveActor, IWithTimers
         // tags registered); production binds the mux via the RuntimeActors extension.
         _dependencyMux?.Tell(msg);
 
-        // Also push the value to the OPC UA sink so the materialised variable reflects live data
-        // instead of staying BadWaitingForInitialData. For SystemPlatform / Galaxy tags the variable
-        // NodeId is exactly the dot-form MXAccess reference the driver subscribed to, so the published
-        // FullReference maps straight onto the sink NodeId.
+        // Also push the value to the OPC UA sink. NOTE: equipment-tag variables are materialised with
+        // folder-scoped NodeIds (EquipmentId/FolderPath/Name), while the driver publishes keyed by
+        // FullReference (the tag's FullName). The value therefore only lands on the variable once the
+        // FullName→NodeId routing — the equipment-tag "live values" milestone — is wired; until then
+        // the variable stays BadWaitingForInitialData. (The retired SystemPlatform mirror matched only
+        // because its NodeId WAS the FullName.)
         _opcUaPublishActor?.Tell(new ZB.MOM.WW.OtOpcUa.Runtime.OpcUa.OpcUaPublishActor.AttributeValueUpdate(
             msg.FullReference, msg.Value, msg.Quality, msg.TimestampUtc));
     }