Complete Qt6 migration: full clean build green across groups G1-G12 incl. runtime plugin set

new_docker_build.sh gains Group 12 (212 GUI/Data plugins); fixes LtsUtilsGuiDds visibility (LTO-stripped exports), LtsProjectionWorkstation unity name shadow, 6 unity-off dirs (dup file-scope statics, ddsftc INTERFACE sources) and reconfigures BUILD_FILTERMANAGEMENT/BUILD_PLUGINS_SERVICEMONITOR=ON

qt6-after/qt6-migrated-legatus/Lts/Proxies/WarehouseManagement/interface_wms2ecc_impl.cpp

@@ -47,7 +47,7 @@ IWMS2ECC::PlayerInfo IWMS2ECC_Impl::convert(const ParticipantManagement::Partici
   pi.alias       = QString::fromStdString(part.identification);
   pi.assignState = convert(part.assignState);
   pi.designator  = QString::fromStdString(part.designator);
-  if (part.equipmentNumber.is_set())
+  if (part.equipmentNumber.has_value())
     pi.equipNo     = part.equipmentNumber.get();
   else if (part.assignState == ParticipantManagement::ParticipantAssignState::HandoutExcon)
     pi.equipNo     = 0;