Switch app code to PyQt6

novelwriter/extensions/pagedsidebar.py

@@ -25,11 +25,11 @@ along with this program. If not, see <https://www.gnu.org/licenses/>.
 """
 from __future__ import annotations
 
-from PyQt5.QtCore import QPoint, QRectF, QSize, Qt, pyqtSignal, pyqtSlot
-from PyQt5.QtGui import QColor, QPainter, QPaintEvent, QPolygon
-from PyQt5.QtWidgets import (
-    QAbstractButton, QAction, QButtonGroup, QLabel, QStyle,
-    QStyleOptionToolButton, QToolBar, QToolButton, QWidget
+from PyQt6.QtCore import QPoint, QRectF, QSize, Qt, pyqtSignal, pyqtSlot
+from PyQt6.QtGui import QAction, QColor, QPainter, QPaintEvent, QPolygon
+from PyQt6.QtWidgets import (
+    QAbstractButton, QButtonGroup, QLabel, QStyle, QStyleOptionToolButton,
+    QToolBar, QToolButton, QWidget
 )
 
 from novelwriter.types import (