docs(galaxy): neutralize remaining stale SystemPlatform/alias terminology in comments + a test name

Replace "SystemPlatform mirror tag", "Galaxy alias", and "SystemPlatform-kind" in doc-comments and
test names with neutral accurate wording ("FolderPath-scoped tag", "EquipmentId == null", etc.).
No code, logic, or test bodies changed — comments and one test method name only.

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

@@ -387,8 +387,7 @@ public sealed class DriverHostActor : ReceiveActor, IWithTimers
         // 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.)
+        // the variable stays BadWaitingForInitialData.
         _opcUaPublishActor?.Tell(new ZB.MOM.WW.OtOpcUa.Runtime.OpcUa.OpcUaPublishActor.AttributeValueUpdate(
             msg.FullReference, msg.Value, msg.Quality, msg.TimestampUtc));
     }