implemented current schoolyear API and dynamic timetable scroll boundaries, added handling for out-of-range errors to narrow accessible dates, optimized holiday region rendering by collapsing overlaps, and refined holiday tile UI

lib/state/app/modules/timetable/data_provider/timetable_data_provider.dart

@@ -11,6 +11,8 @@ import '../../../../../api/mhsl/custom_timetable_event/remove/remove_custom_time
 import '../../../../../api/mhsl/custom_timetable_event/update/update_custom_timetable_event.dart';
 import '../../../../../api/mhsl/custom_timetable_event/update/update_custom_timetable_event_params.dart';
 import '../../../../../api/request_cache.dart';
+import '../../../../../api/webuntis/queries/get_current_schoolyear/get_current_schoolyear_cache.dart';
+import '../../../../../api/webuntis/queries/get_current_schoolyear/get_current_schoolyear_response.dart';
 import '../../../../../api/webuntis/queries/get_holidays/get_holidays_cache.dart';
 import '../../../../../api/webuntis/queries/get_holidays/get_holidays_response.dart';
 import '../../../../../api/webuntis/queries/get_rooms/get_rooms_cache.dart';
@@ -73,6 +75,19 @@ class TimetableDataProvider {
     operationName: 'getSchoolHolidays',
   );
 
+  Future<GetCurrentSchoolyearResponse> getCurrentSchoolyear({
+    void Function(Object)? onError,
+    bool renew = false,
+  }) => resolveFromCache<GetCurrentSchoolyearResponse>(
+    (onUpdate, onError) => GetCurrentSchoolyearCache(
+      renew: renew,
+      onUpdate: onUpdate,
+      onError: onError,
+    ),
+    onError: onError,
+    operationName: 'getCurrentSchoolyear',
+  );
+
   Future<GetTimegridUnitsResponse> getTimegrid({bool renew = false}) =>
       resolveFromCache<GetTimegridUnitsResponse>(
         (onUpdate, _) =>