implemented DST-safe date arithmetic with new addDays and subtractDays extensions, updated timetable state to reset view and scroll boundaries on initialization to prevent stale views, added hard caps to calendar navigation, and updated version to 1.0.3+52

lib/view/pages/timetable/data/calendar_logic.dart

@@ -83,7 +83,7 @@ partitionAppointmentsForWeek(
 ) {
   final inside = List<List<Appointment>>.generate(5, (_) => <Appointment>[]);
   final outside = List<List<Appointment>>.generate(5, (_) => <Appointment>[]);
-  final weekEnd = weekStart.add(const Duration(days: 5));
+  final weekEnd = weekStart.addDays(5);
   final weekStartUtc = weekStart.toUtc();
   final weekEndUtc = weekEnd.toUtc();