Merge feature/qt6-migration-basis-modules-services into feature/qt6-migration-basis-modules

Resolves 17 conflicts against legacy Qt5 semantics; validates with BUILD_RTI=ON BUILD_GRANTLEE=ON.

qt6-after/qt6-migrated-legatus/.forward-declarations/include/DDS/Generic/generic_base.h

@@ -0,0 +1,51 @@
+#pragma once
+
+// Stub header for BUILD_RTI=OFF
+// Original generic_base.h uses RTI Connext DDS types
+
+#include <string>
+#include <ddsgen_export.h>
+#include <QMetaMethod>
+
+// Forward declarations for Qt types used in getMethod
+class QObject;
+
+// Forward declaration for NGL logger
+namespace NGL {
+class INGLLogger;
+}
+
+namespace DDS
+{
+
+// Template for topic type name - returns empty string for BUILD_RTI=OFF
+template<typename T>
+struct topic_type_name {
+    static std::string value() {
+        return "";
+    }
+};
+
+namespace Helper
+{
+// Stub implementations for BUILD_RTI=OFF
+DDSGEN_EXPORT inline std::string getFunctionTopicName(const std::string &fqName) {
+    return fqName;
+}
+
+DDSGEN_EXPORT inline std::string getShortTopicName(const std::string &fqName) {
+    return fqName;
+}
+
+// Stub for getMethod - returns default-constructed QMetaMethod
+DDSGEN_EXPORT inline QMetaMethod getMethod(NGL::INGLLogger & /*logger*/,
+                                           QObject * /*objectToInform*/,
+                                           const char * /*slotToExecute*/,
+                                           const char * /*signalSignature*/,
+                                           bool /*bWarnOnEmptySlot*/ = true) {
+    // Stub implementation - returns default QMetaMethod
+    return QMetaMethod();
+}
+}
+
+} // namespace DDS