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/TetraIF/PrtCnv/LastTest/tetra_if.cpp

@@ -31,7 +31,7 @@ TetraIF::TetraIF(const QHostAddress &addr, unsigned short port, unsigned short i
   , m_timer(nullptr)
   , m_SendCounter(0)
   ),
-    m_logger(NGL::NGLLoggerBootstrap::getLogger()) {
+    m_logger(NGL::NGLLoggerBootstrap::getNGLRootLogger()) {
   connect(m_socket, &QTcpSocket::connected, this, &TetraIF::onConnected);
   connect(m_socket, &QTcpSocket::disconnected,  this, &TetraIF::onDisconnected);
   connect(m_socket, &QTcpSocket::readyRead, this, &TetraIF::onReadyRead);