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/ExerciseManagement/UnitTests/data_topic_tests.cpp

@@ -33,7 +33,7 @@ DataTopicTests::DataTopicTests() : m_domainParticipantPub(nullptr)
   , m_dtcExercise(nullptr)
   , m_mainThreadId(QThread::currentThreadId())
   .getNGLLogger("UnitTests.DataTopicTests")),
-    m_logger(NGL::NGLLoggerBootstrap::getLogger()) {  
+    m_logger(NGL::NGLLoggerBootstrap::getNGLRootLogger()) {  
   if (!DDS::QosProfile::setDefault())
     ERROR_LOG(m_logger) << "Error setting default QoS from xml-file ";