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/Services/OcSituationServer/handler_oc_aes_data.cpp

@@ -282,7 +282,7 @@ void HandlerOcAesData::sendDangerAreasToTab(int eqNumber)
       QByteArray name(QByteArray::fromStdString(dangerArea.name));
       name.resize(8);
       data.append(name);
-      if (dangerArea.effectStart.is_set())
+      if (dangerArea.effectStart.has_value())
         LtsUtils::set4Byte(dangerArea.effectStart.get() / 1000, data);
       else
         LtsUtils::set4Byte(0, data);