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/Viewer/SituationMap/Common/referenced.cpp

@@ -0,0 +1,76 @@
+/**
+**
+** @RDE_HEADER@
+** Base class for reference counted objects
+** $Id$
+** $HeadURL$
+** $Author$
+**
+** -----------------------------------------------------------------------------------------------
+**
+** Hardware-Umgebung: Intel-PC
+** Software-Umgebung: Linux, Windows 7, Qt 5.4. ArcGIS 10.2.5
+**
+** Pgrm-Sprache ....: C++ 11
+**
+** HIER/SACHN ......: P: -- ---- - --- QE
+**
+** Version .........: $Revision$
+** -----------------------------------------------------------------------------------------------
+**
+** Autor ...........: Nikolaus Hanekamp, SEDG, Tel. 2906
+**                    Joerg Turla, SPD G, Tel. 3132
+**
+** -----------------------------------------------------------------------------------------------
+**
+** Notizen .........:
+**
+**   18.08.2004, NH  : Urversion
+**   13.05.2015, JT  : Refactoring for use with Qt5, ArcGIS 10.2.5
+**
+** -----------------------------------------------------------------------------------------------
+*/
+
+
+#include "referenced.h"
+
+#include <QDebug>
+
+#include <typeinfo>
+#include <memory>
+
+
+namespace SituationMap
+{
+
+std::shared_ptr<DeleteHandler> & s_deleteHandler()
+{
+  static std::shared_ptr<DeleteHandler> deleteHandler(nullptr);
+  return deleteHandler;
+} // std::shared_ptr<DeleteHandler> & s_deleteHandler()
+
+
+void Referenced::setDeleteHandler(DeleteHandler *handler)
+{
+  s_deleteHandler().reset(handler);
+} // Referenced::setDeleteHandler
+
+
+DeleteHandler *Referenced::getDeleteHandler() { return s_deleteHandler().get(); }
+
+
+Referenced::~Referenced()
+{
+  if (_refCount > 0)
+  {
+    qCritical() << "Deleting still referenced object < " << QString::number((qint64)this, 0, 16) << ">"
+                <<  "of type <" << typeid(this).name() << ">"
+                <<  "refCnt: <" << _refCount;
+
+  }
+} // Referenced::~Referenced
+
+} // end of namespace SituationMap
+
+
+