migrate from PyQt6 to PySide6, remove unneeded dependencies

src/ui/widgets/__init__.py

@@ -16,7 +16,7 @@ __all__ = [
 
 from .collapse import StatusWidget
 from .filepicker import FilePicker
-from .graph import DataGraph
+from .graph import DataQtGraph
 from .calendar_entry import CalendarEntry
 from .MessageCalendar import MessageCalendar
 from .searchPage import SearchStatisticPage