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/OperatorManagement/opm_dtc.h

@@ -0,0 +1,43 @@
+#pragma once
+
+// STUB-HEADER: Diese Datei wird normalerweise von ddsdtc generiert
+// Für die Migration erstellen wir minimale Implementierungen
+
+#include <QtGlobal>
+#include <string>
+#include <memory>
+
+namespace OperatorManagement
+{
+
+struct User
+{
+  [[nodiscard]] qint32 id() const { return m_id; }
+  [[nodiscard]] std::string name() const { return m_name; }
+
+  qint32 m_id = 0;
+  std::string m_name;
+};
+
+namespace Interface
+{
+class Dtc
+{
+public:
+  // Initialization methods
+  void enableUser() {}
+  void waitForHistoricalDataUser() {}
+  
+  User user(qint32 id) const
+  {
+    // STUB-Implementierung - leerer User
+    User u;
+    u.m_id = id;
+    u.m_name = "Unknown";
+    return u;
+  }
+};
+
+class Ftc;
+} // namespace Interface
+} // namespace OperatorManagement