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/DDS/FTS/generic_fts.h

@@ -3,7 +3,9 @@
 
 #pragma once
 
+#if BUILD_RTI
 #include <rti/core/SampleIdentity.hpp>
+#endif
 #include <QVector>
 
 
@@ -19,8 +21,20 @@ namespace FTS
     GenericFts() = default;
     virtual ~GenericFts() = default;
 
-    virtual bool sendReply(const rti::core::SampleIdentity &requestIdentity, const TOPICTYPE_REPLY &replyData) = 0;
-    virtual bool sendReply(const rti::core::SampleIdentity &requestIdentity, const QVector<TOPICTYPE_REPLY> &replyData) = 0;
+    virtual bool sendReply(
+#if BUILD_RTI
+      const rti::core::SampleIdentity &requestIdentity,
+#else
+      const void *requestIdentity,  // Stub when BUILD_RTI=OFF
+#endif
+      const TOPICTYPE_REPLY &replyData) = 0;
+    virtual bool sendReply(
+#if BUILD_RTI
+      const rti::core::SampleIdentity &requestIdentity,
+#else
+      const void *requestIdentity,  // Stub when BUILD_RTI=OFF
+#endif
+      const QVector<TOPICTYPE_REPLY> &replyData) = 0;
   };
 
 }