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/EffectShowClient/connection_handler_tcp.cpp

@@ -19,7 +19,7 @@ ConnectionHandlerTcp::ConnectionHandlerTcp(QObject *parent) : QObject(parent)
   , m_socket(nullptr)
   , m_timer(new QTimer(this))
   , m_currentDataRead(QByteArray()),
-    m_logger(NGL::NGLLoggerBootstrap::getLogger()) {
+    m_logger(NGL::NGLLoggerBootstrap::getNGLRootLogger()) {
   m_timer->setInterval(5000);
   connect(m_timer, &QTimer::timeout, this, &ConnectionHandlerTcp::open);