fix: scheduled event list init

lib/msc_extensions/msc_4140_delayed_events/models.dart

@@ -9,11 +9,11 @@ class ScheduledDelayedEventsResponse {
 
   factory ScheduledDelayedEventsResponse.fromJson(Map<String, dynamic> json) {
     final list = json['delayed_events'] ?? json['scheduled'] as List;
-    final List<ScheduledDelayedEvent> scheduledEvents =
+    final scheduledEvents =
         list.map((e) => ScheduledDelayedEvent.fromJson(e)).toList();
 
     return ScheduledDelayedEventsResponse(
-      scheduledEvents: scheduledEvents,
+      scheduledEvents: List<ScheduledDelayedEvent>.from(scheduledEvents),
       nextBatch: json['next_batch'] as String?,
     );
   }