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/DDS/DdsUnitTests/data_topic_tests.h

@@ -0,0 +1,72 @@
+/**
+  * @RDE_HEADER@
+  * Unit test for DataTopic Server & Client (DTS & DTC)
+  * $Id$
+  * $HeadURL$
+  * $Author$
+  * Created by Hanna E. Rathje, SLSE, 2015-07-24
+  */
+#pragma once
+
+#include <QObject>
+#include <DDS/Generic/subscriber_listener.h>
+
+#include <DdsUnitTests/ddsut_dtc_types.h>
+#include <DdsUnitTests/ddsut_dts_types.h>
+
+
+namespace NGL {
+  class INGLLogger;
+}
+
+class DataTopicTests : public QObject
+{
+  Q_OBJECT
+public:
+  DataTopicTests();
+  virtual ~DataTopicTests();
+
+  // Initialisation
+  bool initPublisher();
+  bool initSubscriber();
+
+  // Publisher
+  bool write(const DdsUnitTests::TestParticipant &data);
+
+  // Subscriber  
+  DdsUnitTests::TestParticipant getReceivedParticipantData() const { return m_receivedParticipantData; }
+  void deleteDTC();
+  void deleteSubscriber();
+
+protected:
+  // Subscriber Methods  
+  void processData(const DdsUnitTests::TestParticipant &instance, const dds::sub::SampleInfo &si);
+
+Q_SIGNALS:  
+  void testParticipantDataArrived();
+
+private:
+  dds::domain::DomainParticipant  m_domainParticipantPub;
+  dds::domain::DomainParticipant  m_domainParticipantSub;
+  int                             m_domainId;
+  int                             m_partitionId;
+
+  // Publisher
+  dds::pub::Publisher             m_ddsPublisher;  
+  DTS::TestParticipant           *m_testPart;
+
+  // Subscriber
+  dds::sub::Subscriber            m_ddsSubscriber;  
+  DDSGeneric::SubscriberListener *m_subscriberListener;
+
+  DTC::SampleInfo::TestParticipant *m_dtcTestPart;
+
+  Qt::HANDLE                      m_mainThreadId;
+  // For returning TestData
+  DdsUnitTests::TestParticipant   m_receivedParticipantData;
+
+  NGL::INGLLogger&                m_logger;
+};
+
+
+