BUILD_RTI conditional fixes and Qt6 API updates

- cmake/FindRTI.cmake: Add INTERFACE placeholder targets when RTI not found
- cmake/FindRTI.cmake: Force BUILD_RTI=OFF when RTI not installed
- Lts/Common/LtsSession/CMakeLists.txt: Make LtsSessionDataDds conditional on BUILD_RTI
- Lts/Viewer/CMakeLists.txt: Make LtsDataView conditional on BUILD_RTI
- Lts/Plugins/*/CMakeLists.txt: 97 plugin files wrapped in BUILD_RTI conditionals
- cmake/NGLMacros.cmake: Fix NGL_ADD_BIG_RESOURCES macro (removed premature return())
- Multiple Qt6 API fixes: QLinkedList→std::list, QStringRef→QStringView, etc.
- BUILD_RTI_FIXES_SUMMARY.md: Comprehensive documentation of all fixes

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

qt6-after/qt6-migrated-legatus/Lts/Services/AudioVideoManagement/ModuleTests/avm_vca_tests.cpp

@@ -41,7 +41,7 @@ AvmVcaTests::AvmVcaTests(int domainId, int exerciseId, int operatorId)
   : m_ddsConnector(std::make_shared<DDSConnector::DdsConnector>(domainId, IDL::PartitionType::Exercise))
   , m_exerciseId(exerciseId)
   , m_operatorId(operatorId)
-  , m_logger(NGL::NGLLoggerBootstrap::getNGLRootLogger().getNGLLogger("VcaTest"))
+  .getNGLLogger("VcaTest"))
 {
   Q_ASSERT(exerciseId > 0);
   Q_ASSERT(operatorId > 0);