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/resource_path.cpp

@@ -0,0 +1,51 @@
+/**
+  * @RDE_HEADER@
+  * Helper function to get the resource path
+  * $Id$
+  * $HeadURL$
+  * $Author$
+  */
+
+
+#include "resource_path.h"
+
+
+#include <ngltools/ngltools_filesystem.h> // for NGL::directories
+
+
+// Qt
+#include <QDir>
+#include <QVector>
+
+
+//----------------------------------------------------------------------------
+namespace SituationMap
+{
+
+
+QString getResourcePath()
+{
+  const QString resDir = NGL::directory(NGL::FileType::ConfigFile, QLatin1String("resources"));
+  if (!resDir.isEmpty())
+    return resDir;
+
+  QVector<QString> pathsToSearch;
+
+  // for old systems
+#ifdef Q_OS_WIN
+  pathsToSearch += QLatin1String("C:/ExtFw/resources/");
+#else
+  pathsToSearch += QLatin1String("/usr/share/arcgis/resources");
+#endif
+
+  for (const QString &path : qAsConst(pathsToSearch))
+  {
+    if (QDir(path).exists())
+      return path + QLatin1Char('/');
+  }
+  return QString();
+}
+
+
+} // namespace SituationMap
+