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/Application/OpApp/main.cpp

@@ -36,7 +36,6 @@
 #include <QInputDialog>
 #include <QNetworkProxy>
 #include <QtCore/QTimer>
-#include <QRandomGenerator>
 #include <QInputDevice>
 #include <algorithm>
 
@@ -175,7 +174,10 @@ public:
 // ------------------------------------------------------------------
 int main(int argc, char **argv) // TODO: json strings to lower
 {
-  QRandomGenerator::global()->seed(time(nullptr));
+  // (legacy: qsrand(time(nullptr));) — the Qt5 global RNG (qrand/qsrand) does not exist in Qt6.
+  // QRandomGenerator::global() is auto-seeded (non-deterministically) by Qt, and calling ->seed()
+  // on the global/system generator aborts in Qt 6.10 ("Attempted to overwrite a QRandomGenerator to
+  // system() or global()"), so no explicit seed is needed here.
 
   QCoreApplication::setAttribute(Qt::AA_UseDesktopOpenGL);