Qt6 Migration: Merge latest Qt5 devel content and apply migration fixes

- Merged 292 changed files from dlbo snapshot
- Fixed IDL enum collisions (PortType, PdmEventType)
- Fixed Grantlee template for C++11 scoped enums
- Fixed CMake VERSION_GREATER syntax
- Added missing directories (THP, LtsRestClient, etc.)

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

Lts/Tools/Examples/Plugins/interfaces/parent_interface.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <QString>
+#include <QWidget>
+#include <QtPlugin>
+
+class ParentInterface
+{
+  public:
+  virtual ~ParentInterface() = default;
+  virtual QString pluginName() const = 0;
+  virtual QWidget *widget() = 0;
+  virtual void addChildWidget(QWidget *childWidget) = 0;
+
+  // Ermöglicht der App den Zugriff auf das QObject für connect()
+  virtual QObject *qobjectInstance() = 0;
+};
+
+QT_BEGIN_NAMESPACE
+Q_DECLARE_INTERFACE(ParentInterface, "gui:3:ParentInterface")
+QT_END_NAMESPACE
+