fix(live_room): 解决直播房间页面关闭时小窗口显示问题

- 添加 Assets.imagesUserAvatar 资源导入
- 修复页面关闭时 Get.back() 重复调用问题
- 添加延迟机制确保小窗口在页面关闭后正确显示
- 修复主播信息为空时的空指针异常
- 设置默认用户名和头像资源作为备选值

lib/pages/discover/live_room_page.dart

@@ -1,6 +1,7 @@
 import 'package:dating_touchme_app/controller/discover/room_controller.dart';
 import 'package:dating_touchme_app/controller/global.dart';
 import 'package:dating_touchme_app/controller/overlay_controller.dart';
+import 'package:dating_touchme_app/generated/assets.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:tdesign_flutter/tdesign_flutter.dart';
@@ -241,8 +242,14 @@ class _LiveRoomPageState extends State<LiveRoomPage> {
           final roomController = Get.find<RoomController>();
           roomController.chatMessages.clear();
         }
-        _overlayController.show();
-        Get.back();
+        // 如果还没有执行 pop，手动调用 Get.back()
+        if (!didPop) {
+          Get.back();
+        }
+        // 等待页面关闭后再显示小窗口，确保小窗口能正确显示
+        Future.delayed(const Duration(milliseconds: 200), () {
+          _overlayController.show();
+        });
       },
       child: Scaffold(
         resizeToAvoidBottomInset: false,
@@ -281,8 +288,8 @@ class _LiveRoomPageState extends State<LiveRoomPage> {
                     final detail = _roomController.rtcChannelDetail.value;
                     final anchorInfo = detail?.anchorInfo;
 
-                    final userName = anchorInfo!.nickName;
-                    final avatarAsset = anchorInfo.profilePhoto;
+                    final userName = anchorInfo?.nickName ?? '用户';
+                    final avatarAsset = anchorInfo?.profilePhoto ?? Assets.imagesUserAvatar;
                     const popularityText = '0'; // TODO: 使用真实数据
 
                     return LiveRoomUserHeader(
@@ -296,8 +303,11 @@ class _LiveRoomPageState extends State<LiveRoomPage> {
                           final roomController = Get.find<RoomController>();
                           roomController.chatMessages.clear();
                         }
-                        _overlayController.show();
                         Get.back();
+                        // 等待页面关闭后再显示小窗口，确保小窗口能正确显示
+                        Future.delayed(const Duration(milliseconds: 200), () {
+                          _overlayController.show();
+                        });
                       },
                     );
                   }),