Qt6 Migration: BUILD_RTI guards und CMake fixes

- BUILD_RTI conditional compilation für RTI Connext DDS dependencies
- Namespace fixes in core_dtc.h (Core:: → DDS::Core::)
- CMakeLists.txt: BUILD_RTI option und conditional dependencies
- Handler minelayer: namespace closing mit BUILD_RTI guard
- Build erfolgreich mit BUILD_RTI=OFF validiert

Signed-off-by: Torsten Wierschin <torsten.wierschin@life-maps.com>

qt6-after/qt6-migrated-legatus/Lts/Services/OcBaseDownload/pdf_download_socket.cpp

@@ -19,7 +19,7 @@ PdfDownloadSocket::PdfDownloadSocket(const QString &hostName, QObject *parent) :
   , m_socket(new QTcpSocket(this))
   , m_readTimeout(new QTimer(this))
   , m_sizeToDownload(0),
-    m_logger(NGL::NGLLoggerBootstrap::getLogger()) {
+    m_logger(NGL::NGLLoggerBootstrap::getNGLRootLogger()) {
   DEBUG_LOG(m_logger) << "PdfDownloadSocket::PdfDownloadSocket";
   connect(m_socket, &QTcpSocket::connected, this, &PdfDownloadSocket::connected);
   connect(m_socket, &QTcpSocket::readyRead, this, &PdfDownloadSocket::readyRead);