improved performance and battery usage on older devices

lib/state/app/modules/chat/bloc/chat_bloc.dart

@@ -59,6 +59,12 @@ class ChatBloc
   @override
   ChatState fromStorage(Map<String, dynamic> json) => ChatState.fromJson(json);
 
+  // Loading-older and reply-reference flips must not re-persist up to 500
+  // messages; GetChatResponse has no `==`, so it compares by identity here.
+  @override
+  Object? persistenceKey(ChatState data) =>
+      (data.currentToken, data.chatResponse, data.hasMoreOld);
+
   @override
   Map<String, dynamic>? toStorage(ChatState state) {
     final response = state.chatResponse;