Mirror VirtualTagHostActor's _nodeIdByVtag pattern for driver values: a shared
EquipmentNodeIds helper (kills the duplicated formula), DriverInstanceId on
AttributeValuePublished, and a (DriverInstanceId,FullName)->NodeId[] map built +
resolved in DriverHostActor.ForwardToMux. No OpcUaPublishActor change.
Driver-value delivery only; native alarms + historian remain separate.
Joseph Doherty