Lts/Tools: Complete QRegExp to QRegularExpression migration

- Migrated QRegExp → QRegularExpression in:
  - DdsView/detailview.cpp (line 636)
  - DdsView/sequences/abstractsequencewidget.cpp (line 167)
  - VapixConfig/httprequesthandler.cpp (lines 68, 95, 136)
  - ConfigX/configurator.cpp
  - LogViewer/sortfiltermodel.cpp
  - SqlBrowser/BrowserWnd.cpp
- Added Qt6::Core5Compat to TextEditorTest CMakeLists.txt for QTextCodec support
- All QRegExp instances in Lts/Tools now migrated to QRegularExpression

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

qt6-after/qt6-migrated-legatus/Lts/Tools/DdsView/sequences/abstractsequencewidget.cpp

@@ -8,6 +8,7 @@
   */
 #include "abstractsequencewidget.h"
 
+#include <QRegularExpression>
 #include <QToolButton>
 
 AbstractSequenceWidget::AbstractSequenceWidget(const RwMode &readOnly,
@@ -164,7 +165,7 @@ void AbstractSequenceWidget::deleteMemberWidget(QObject *member)
 
       QString childName = child->objectName();
       QString newId = m_name + QLatin1Char('.') + QString::number(i + 1);
-      child->setObjectName(childName.replace(QRegExp(m_name + QLatin1String(".([0-9]*)")), newId));
+      child->setObjectName(childName.replace(QRegularExpression(QRegularExpression::escape(m_name + QLatin1String(".") + "([0-9]*)")), newId));
       DEBUG_LOG(m_logger) << "new child name: " << child->objectName();
     }
   }