Grantlee Templates: Fix namespace resolution for RTI DTC generation

- Changed {{ namespace }}::{{ dt.type }} to ::{{ namespace }}::{{ dt.type }}
  in svc_dtc.h.grantlee, svc_dtc_impl.cpp.grantlee, svc_dtc_impl.h.grantlee
- Ensures absolute namespace resolution for Core::* types
- Fixes MOC/compilation errors for CurrentRunningState, LockedEntity, etc.

- Updated CMakeLists.txt for RTI 7.7.0 detection with DDS_PATH
- Fixed RTI include paths (ndds/hpp and ndds directories)
- Updated Lts/DDS module files for Qt6/RTI 7.7 compatibility

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

qt6-after/qt6-migrated-legatus/Lts/DDS/DDSConnector/subscriber.cpp

@@ -4,7 +4,7 @@
 #include "subscriber.h"
 #include "pub_sub_base_p.h"
 
-#include <DDS/QosProfile/DDS_DefaultQos.h>
+#include <Lts/DDS/QosProfile/DDS_DefaultQos.h>
 #include <NGLLogger/INGLLogger.h>
 
 namespace DDSConnector