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/Proxies/TrainingAreaBaseOC/websocket_handler.h

@@ -0,0 +1,55 @@
+#pragma once
+
+#include "dds_handler.h"
+#include "logger.h"
+#include <taboc_dtc.h>
+#include <QWebSocket>
+
+class QTimer;
+
+namespace TrainingAreaBaseOC {
+
+enum class WebSocketState {
+  DISCONNECTED = 0, // should not happen
+  CONNECTEDTOSERVER, // 1
+  CONNECTTOPPM, // 2
+  CONNECTEDTOPPM, // 3
+};
+
+class WebsocketHandler : public QObject
+{
+  Q_OBJECT
+public:
+  WebsocketHandler(QObject *parent, int exerciseId,
+                   const std::shared_ptr<Interface::Dts> dtsTabOc, const std::shared_ptr<Interface::Dtc> dtcTabOc);
+
+private slots:
+  void onTryConnectionTimerTimeout();
+  void onFetchPositionTimerTimeout();
+  void onNewSocketState(QAbstractSocket::SocketState state);
+  void onNewTextMessageFromSocket(const QString &message);
+
+private:
+  void connectToExPPM(int exPort);
+  void sendPositionRequest();
+  void onSendOwnPosition(const QString &message);
+
+  void connectToServer();
+  void sendServicePortRequest();
+  void parseServices(const QString &message);
+
+  WebSocketState m_state = WebSocketState::DISCONNECTED;
+  int m_exerciseId = 0;
+  int m_ownEquipmentId = 0;
+  std::shared_ptr<Interface::Dts> m_dtsTaboc;
+  std::shared_ptr<Interface::Dtc> m_dtcTaboc;
+  QTimer *m_tryConnectionTimer = nullptr;
+  QTimer *m_fetchPositionTimer = nullptr;
+  QWebSocket *m_socket = nullptr;
+
+  LOGGER_T &m_logger;
+
+};
+
+
+} // namespace TrainingAreaBaseOc