Qt6 migration: Fix BUILD_RTI=OFF build errors in TrainingAreaBase

- training_area_telegrams.cpp: Fixed QJsonObject initializer syntax (Qt6 requires {{}} not ({}))
- training_area_telegrams.cpp: Fixed fromJson() methods to access m_* members directly
- training_area_telegrams.cpp: Fixed brace mismatches in multiple toJson() methods
- training_area_telegrams.h: Changed Header struct to public members for consistency
- tx_mixin.cpp: Fixed getEquipmentNumber() template for direct member access
- lts_coordinate.cpp: Added missing #include <iomanip>
- MIGRATION_STATUS.md: Added migration progress tracking document

C++17 constraint enforced due to RTI Connext DDS 7.7.0 incompatibility with C++20+

Build status: BUILD_RTI=OFF successful (0 errors, warnings only)

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

qt6-after/qt6-migrated-legatus/Lts/Plugins/PlanOverlays/Gui/TopicEditor/topic_editor.cpp

@@ -9,11 +9,11 @@
 #include <NGLLogger/NGLLoggerBootstrap.h>
 #include <TopicEditorBase/topic_previewer.h>
 
-#include <QInputDialog>
-#include <QJsonObject>
-#include <QJsonArray>
-#include <QMessageBox>
-#include <QPushButton>
+#include <QtWidgets/QInputDialog>
+#include <QtCore/QJsonObject>
+#include <QtCore/QJsonArray>
+#include <QtWidgets/QMessageBox>
+#include <QtWidgets/QPushButton>
 
 
 namespace PlanOverlaysPlugin

qt6-after/qt6-migrated-legatus/Lts/Plugins/PlanOverlays/Gui/TopicEditor/topic_editor.h

@@ -8,7 +8,7 @@
 #include <LtsSession/lts_session.h>
 #include <TopicEditorBase/topic_editor_base.h>
 
-#include <QJsonArray>
+#include <QtCore/QJsonArray>
 
 
 namespace Ui { class PlanTopicEditor; }

qt6-after/qt6-migrated-legatus/Lts/Plugins/PlanOverlays/Gui/plan_overlay_dialog.cpp

@@ -14,7 +14,7 @@
 
 #include <Viewer/LtsFileDialog/lts_file_dialog_widget.h>
 
-#include <QDebug>
+#include <QtCore/QDebug>
 #include <QtWidgets/QApplication>
 #include <QtWidgets/QDesktopWidget>
 #include <QtWidgets/QDialog>

qt6-after/qt6-migrated-legatus/Lts/Plugins/PlanOverlays/Gui/plan_overlay_model.cpp

@@ -4,10 +4,10 @@
 #include "plan_overlay_model.h"
 #include <utility>
 
-#include <QByteArray>
-#include <QDataStream>
+#include <QtCore/QByteArray>
+#include <QtCore/QDataStream>
 #include <QMimeData>
-#include <QJsonArray>
+#include <QtCore/QJsonArray>
 
 #include <FileManagement/flm_dtc.h>
 #include <NGLLogger/NGLLoggerBootstrap.h>

qt6-after/qt6-migrated-legatus/Lts/Plugins/PlanOverlays/Gui/plan_overlay_model.h

@@ -6,8 +6,8 @@
 #include <Plugins/SituationMapPlugin/situation_map_gui_plugin_interface.h>
 #include <NGLLogger/INGLLogger.h>
 
-#include <QAbstractItemModel>
-#include <QJsonObject>
+#include <QtCore/QAbstractItemModel>
+#include <QtCore/QJsonObject>
 
 
 namespace PlanOverlaysPlugin

qt6-after/qt6-migrated-legatus/Lts/Plugins/PlanOverlays/Gui/plan_overlays_gui_plugin.cpp

@@ -31,16 +31,16 @@
 #include <Viewer/SituationMap/Map/map.h>
 #include <Viewer/SituationMap/GeometryModel/geometry_model_factory.h>
 
-#include <QCoreApplication>
-#include <QDateTime>
-#include <QFile>
-#include <QPointer>
-#include <QStandardPaths>
-#include <QHBoxLayout>
-#include <QMainWindow>
+#include <QtCore/QCoreApplication>
+#include <QtCore/QDateTime>
+#include <QtCore/QFile>
+#include <QtCore/QPointer>
+#include <QtCore/QStandardPaths>
+#include <QtWidgets/QHBoxLayout>
+#include <QtWidgets/QMainWindow>
 #include <QtGlobal>
 
-#include <QDebug>
+#include <QtCore/QDebug>
 
 #include <iostream>
 

qt6-after/qt6-migrated-legatus/Lts/Plugins/PlanOverlays/Gui/plan_overlays_gui_plugin.h

@@ -12,7 +12,7 @@
 #include <Plugins/FileManagement/flm_data_plugin_interface.h>
 #include <Plugins/ExerciseManagement/exm_data_plugin_interface.h>
 
-#include <QObject>
+#include <QtCore/QObject>
 
 
 namespace Core

qt6-after/qt6-migrated-legatus/Lts/Plugins/PlanOverlays/plan_overlays_plugin_interface.h

@@ -6,8 +6,8 @@
 #include <PluginInterfaces/topic_replay_interface.h>
 #include <TopicEditorBase/topic_editor_interface.h>
 
-#include <QJsonArray>
-#include <QJsonObject>
+#include <QtCore/QJsonArray>
+#include <QtCore/QJsonObject>
 
 
 namespace SituationMap