sendImageMessage method
发送图片消息
web 端发送图片消息时需要传入fileName、fileContent 字段
Implementation
Future<V2TimValueCallback<V2TimMessage>> sendImageMessage(
{required String imagePath,
required String receiver,
required String groupID,
int priority = 0,
bool onlineUserOnly = false,
bool isExcludedFromUnreadCount = false,
Map<String, dynamic>? offlinePushInfo,
String? fileName,
Uint8List? fileContent}) async {
throw UnimplementedError("sendImageMessage() has not been implemented");
}