重构事件信息页面，移除不必要的加载状态和错误消息字段，简化状态管理逻辑；在扫码页面中增强选手信息查询功能，添加加载提示和错误处理。

lib/features/events/state/state_event_info.dart

@@ -2,17 +2,13 @@ import 'package:recording_tool/features/events/model/model_event_info.dart';
 
 class EventInfoState {
   const EventInfoState({
-    this.isLoading = false,
     this.isRequestingStreamKey = false,
-    this.errorMessage,
     this.profile = const EventProfile(name: '', phone: '', eventTitle: '赛事信息'),
     this.total = 0,
     this.items = const [],
   });
 
-  final bool isLoading;
   final bool isRequestingStreamKey;
-  final String? errorMessage;
   final EventProfile profile;
   final int total;
   final List<EventRegistrationItem> items;
@@ -21,21 +17,14 @@ class EventInfoState {
       items.isEmpty ? profile.eventTitle : items.first.eventName;
 
   EventInfoState copyWith({
-    bool? isLoading,
     bool? isRequestingStreamKey,
-    String? errorMessage,
-    bool clearErrorMessage = false,
     EventProfile? profile,
     int? total,
     List<EventRegistrationItem>? items,
   }) {
     return EventInfoState(
-      isLoading: isLoading ?? this.isLoading,
       isRequestingStreamKey:
           isRequestingStreamKey ?? this.isRequestingStreamKey,
-      errorMessage: clearErrorMessage
-          ? null
-          : (errorMessage ?? this.errorMessage),
       profile: profile ?? this.profile,
       total: total ?? this.total,
       items: items ?? this.items,