Qt6 Migration: Complete migration with DDS/RTI support and build validation

Major Changes:
- Merged latest Qt5 devel content from dlbo (292 files changed, 7 new dirs)
- Consolidated forward-declarations and include folders
- Removed unneeded modules per Niklas' repo check list

Build System Fixes:
- Fixed CMake VERSION_GREATER syntax in ParticipantManagement/CMakeLists.txt
- Added VLC packages (libvlc-dev, vlc-plugin-base) to docker_build.sh
- Added PostgreSQL dev packages (libpq-dev, postgresql-server-dev-all) to Dockerfile
- Fixed locale warnings (ANSI_X3.4-1968 → C.UTF-8)
- Fixed ArcGIS SDK path warnings when BUILD_ARCGIS=OFF

Code Generation Fixes:
- Fixed IDL enum collisions (PortType→CorePortType/DdsutPortType, PdmEventType)
- Fixed Grantlee template svc_translation.cpp.grantlee:
  - Changed {{ idl_enum.name }}_def:: to {{ idl_enum.name }}::
  - Fixed .underlying() calls for C++11 scoped enums (enum class)
- Removed generated files from repo (moc_*, *_dtc.h, *_ftc.h)

Validation:
- BUILD_RTI=ON: SUCCESS
- BUILD_RTI=OFF: SUCCESS
- C++17 standard maintained for RTI 7.7 compatibility
- Ubuntu 26.04 Docker environment verified

Remaining Warnings (expected):
- BgViewer, KDChart, KDReports, Poppler-Qt6 not found (optional features)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

qt5-before/dlbo/Lts/Common/LtsWidgets/lts_tool_box.cpp

@@ -0,0 +1,90 @@
+/**
+* @RDE_HEADER@
+* ToolBox for Menus
+* $Id$
+* $HeadURL$
+* $Author$
+*/
+
+#include "lts_tool_box.h"
+
+#include "lts_drag_icon.h"
+#include "lts_grid_layout.h"
+
+#include <QMenu>
+#include <QScroller>
+#include <QScrollArea>
+
+using namespace LtsWidgets;
+
+
+LtsToolBox::LtsToolBox(QWidget *parent)
+  : QToolBox(parent)
+{
+
+  setMinimumSize(17, 200);
+  setContextMenuPolicy(Qt::CustomContextMenu);
+  connect(this, &LtsToolBox::customContextMenuRequested,
+          this, &LtsToolBox::showContextMenu);
+
+  setSizePolicy(QSizePolicy::Minimum, QSizePolicy::Minimum);
+
+}
+
+LtsToolBox::~LtsToolBox()
+{
+}
+
+void LtsToolBox::resizeEvent(QResizeEvent *e)
+{
+  emit resized(e);
+  QToolBox::resizeEvent(e);
+
+}
+
+void LtsToolBox::addItem(QWidget *widget, const QString &text)
+{
+  setMinimumSize(120, 100);
+  QToolBox::addItem(widget, text);
+}
+
+
+void LtsToolBox::showContextMenu(const QPoint &pos)
+{
+
+  // for most widgets
+  QPoint globalPos = this->mapToGlobal(pos);
+  // for QAbstractScrollArea and derived classes you would use:
+  // QPoint globalPos = myWidget->viewport()->mapToGlobal(pos);
+
+  QMenu myMenu;
+  myMenu.addAction(tr("Icon and Text"));
+  QAction *to = myMenu.addAction(tr("Text Only"));
+  QAction *io = myMenu.addAction(tr("Icon Only"));
+
+
+  QAction *selectedItem = myMenu.exec(globalPos); // TODO: use popup, use signals & slots
+  if (selectedItem)
+  {
+    ButtonStyle newStyle = ButtonStyle::eTextNextToIcon;
+    if (selectedItem == to)
+      newStyle = ButtonStyle::eTextOnly;
+    if (selectedItem == io)
+      newStyle = ButtonStyle::eIconOnly;
+
+    for (int i = 0; i < count(); i++)
+    {
+      const QList<LtsDragIcon *> list  = widget(i)->findChildren<LtsDragIcon *>();
+      for (LtsDragIcon *icon : list)
+        icon->setButtonStyle(newStyle);
+      LtsGridLayout *lay = qobject_cast<LtsGridLayout *>(widget(i)->layout());
+      if (lay)
+        lay->setAutoSize((newStyle == ButtonStyle::eIconOnly));
+    }
+
+  }
+  else
+  {
+    // nothing was chosen
+  }
+}