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/Tools/DdsView/mainwindow.h

@@ -0,0 +1,102 @@
+/**
+  * @RDE_HEADER@
+  *
+  * MainWindow for DDS View
+  *
+  * $Id$
+  * $HeadURL$
+  * $Author$
+  */
+
+#pragma once
+
+#include "initialisation.h"
+
+#include <nglwidgets/nglmainwindow.h>
+#include <DDS/DDSConnector/subscriber.h>
+#include <QVariant>
+#include <QItemSelection>
+
+namespace Ui
+{
+class MainWindow;
+}
+
+namespace DdsView
+{
+class Initialisation;
+}
+
+namespace LtsPluginManager
+{
+struct PluginInstance;
+}
+
+class TopicDataModel;
+class TopicSortModel;
+class TopicDiscoverer;
+struct TopicDescriptionEx;
+class TreeItem;
+class TreeModel;
+
+// --------------------------------------------------------------------------------
+// |                                Class MainWindow                              |
+// --------------------------------------------------------------------------------
+class MainWindow : public NGLMainWindow
+{
+  Q_OBJECT
+
+public:
+  explicit MainWindow(int domainId, int exerciseId,
+                      DDS::QosProfile::ConnectionType ct, const QUrl &tcpDiscoveryUrl,
+                      QWidget *parent = nullptr);
+  ~MainWindow();
+
+private:
+  TreeItem *getServiceKnot(TopicDescriptionEx &description, TreeModel *modelToSearch) const;
+  struct DdsCredentials
+  {
+    int exercise = 0;
+    int domain   = 0;
+    IDL::PartitionType partitionType = IDL::PartitionType::Exercise;
+    QVector<DDSGeneric::TopicDescription> droTypes;
+
+    bool operator ==(const DdsCredentials &o) const
+    {
+      return (exercise == o.exercise && domain == o.domain && droTypes == o.droTypes && partitionType == o.partitionType);
+    }
+    DdsCredentials(int e = 0, int d = 0, IDL::PartitionType p = IDL::PartitionType::Exercise, const QVector<DDSGeneric::TopicDescription> &s = QVector<DDSGeneric::TopicDescription>())
+      : exercise(e)
+      , domain(d)
+      , partitionType(p)
+      , droTypes(s)
+    {}
+  };
+
+  DdsView::Initialisation *m_dsr;
+  DdsCredentials           m_ddsCredentials;
+  TopicDiscoverer         *m_topicDiscoverer;
+  TopicSortModel          *m_dataSortModel;
+  TopicSortModel          *m_functionSortModel;
+  TopicDataModel          *m_topicDataModel;
+  Ui::MainWindow          *m_ui;
+  TreeModel               *m_treeSrcModelData;
+  TreeModel               *m_treeSrcModelFunction;
+
+  void setVersionView();
+  void loadPlugins();
+  void updateButtons(const DdsCredentials &current);
+  bool loadPlugin(const LtsPluginManager::PluginInstance &pi);
+
+  IDL::PartitionType partitionType() const;
+private slots:
+  DdsCredentials onReaderChanged();
+  void onSelectionFunctionChanged(const QItemSelection &selected, const QItemSelection &deselected);
+  void onSend(const QSharedPointer<dds::core::xtypes::DynamicData> &data, const QString &topicName);
+  void onConnect();
+  void onDisconnect();
+  void onConfigureDetails();
+  void onTopicDescription(const std::string &topicName,
+                          const std::string &typeName,
+                          const dds::core::xtypes::StructType &type);
+};