Qt6 Migration: LtsWidgets, BUILD_RTI Guards, externe Dependencies dokumentiert

- LtsWidgets Verzeichnis vollständig migriert (Qt5→Qt6)
- BUILD_RTI Guards für RTI-spezifische Module hinzugefügt
- Externe Dependencies in EXTERNAL_DEPS.md dokumentiert
- Qt6 API-Änderungen: QRegExp→QRegularExpression, enterEvent(QEnterEvent*)
- AutoUic-Fehler bei ui_requirement behoben (SKIP_AUTOUIC)
- Include-Pfade korrigiert (LtsElevation, LtsMultiMonitor, LtsUtilsCore)
- MOC-Fehler behoben (Q_INTERFACES entfernt wo nicht benötigt)
- CMakeLists.txt Anpassungen für Qt6 (PUBLIC statt INTERFACE)

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

qt6-after/qt6-migrated-legatus/Lts/Plugins/TakeHomePackageManager/THP2/Common2Core/CMakeLists.txt

@@ -21,6 +21,8 @@ NGL_TARGET_INCLUDE_DIRECTORIES(Thp2CommonCore
   PUBLIC
     ${CMAKE_CURRENT_SOURCE_DIR}/../
     ${CMAKE_CURRENT_BINARY_DIR}/../ # export file
+    ${CMAKE_SOURCE_DIR}/Lts/Common
+    ${CMAKE_SOURCE_DIR}/Lts/Common/LtsUtils
 )
 NGL_TARGET_LINK_LIBRARIES(Thp2CommonCore
   PRIVATE