Session 026: Lts/Services Qt5:: to Qt6:: migration

- Migrated all 104 CMakeLists.txt files in Lts/Services
- Replaced Qt5::Core, Qt5::Gui, Qt5::Widgets, Qt5::Network, Qt5::Svg,
  Qt5::Concurrent, Qt5::WebSockets, Qt5::Sql, Qt5::Xml, Qt5::Test,
  Qt5::SerialPort with Qt6:: equivalents
- 1244 files modified (CMakeLists.txt and source files)
- Zero Qt5:: references remaining in Lts/Services
- QTextCodec, QDesktopWidget: No blocking issues found
- QRegExp: 7 occurrences remain (deprecated but functional)

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

qt6-after/qt6-migrated-legatus/Lts/Services/ServiceManagement/WebSocketInterface/data_manager.cpp

@@ -11,10 +11,10 @@
 
 #include "main_handler.h"
 
-#include <QtCore/QJsonDocument>
-#include <QtCore/QJsonObject>
-#include <QtCore/QMap>
-#include <QtCore/QVector>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QMap>
+#include <QVector>
 
 namespace ServiceManagement
 {