improved performance and battery usage on older devices

lib/state/app/modules/timetable/bloc/week_cache.dart

@@ -1,13 +1,12 @@
-import 'package:collection/collection.dart';
-
 import '../../../../../api/marianumconnect/queries/timetable_get_week/timetable_get_week_response.dart';
 import '../../../../../extensions/date_time.dart';
+import '../../../../../utils/json_equality.dart';
 
 /// Weeks kept around the viewed week and around today's week. Everything
 /// further away is dropped: every state emit re-serializes the whole cache for
 /// HydratedBloc and the calendar rebuilds its appointments from all of it, so
 /// an unbounded cache makes week swipes slower the longer the app is used.
-const int kWeekCacheRadius = 4;
+const int kWeekCacheRadius = 8;
 
 /// Returns the cache with [week] stored under [weekStart], pruned to the
 /// weeks near [viewedWeekStart] or [now]. Returns null when the stored week
@@ -21,10 +20,7 @@ Map<String, TimetableGetWeekResponse>? mergeWeekIntoCache(
 }) {
   final key = weekStart.weekKey();
   final existing = cache[key];
-  if (existing != null &&
-      const DeepCollectionEquality().equals(existing.toJson(), week.toJson())) {
-    return null;
-  }
+  if (sameJson(existing, week)) return null;
 
   final viewedMonday = viewedWeekStart.mondayOfWeek;
   final todayMonday = now.mondayOfWeek;