前端：

1、优化消息排序逻辑
2、新增加载历史消息
3、修复已知问题
后端：
1、优化消息排序逻辑
2、增加用户信息缓存机制
3、修改日期类型为DateTimeOffset改善时区信息丢失问题
3、修复了已知问题
数据库：
1、新增SequenceId字段用于消息排序
2、新增ClientMsgId字段用于客户端消息回执

backend/IM_API/Application/EventHandlers/MessageCreatedHandler/MessageCreatedDbHandler.cs

@@ -0,0 +1,26 @@
+using IM_API.Domain.Events;
+using MassTransit;
+using IM_API.Interface.Services;
+using AutoMapper;
+using IM_API.Models;
+
+namespace IM_API.Application.EventHandlers.MessageCreatedHandler
+{
+    public class MessageCreatedDbHandler : IConsumer<MessageCreatedEvent>
+    {
+        private readonly IMessageSevice _messageService;
+        public readonly IMapper _mapper;
+        public MessageCreatedDbHandler(IMessageSevice messageSevice, IMapper mapper)
+        {
+            _messageService = messageSevice;
+            _mapper = mapper;
+        }
+
+        public async Task Consume(ConsumeContext<MessageCreatedEvent> context)
+        {
+            var @event = context.Message;
+            var msg = _mapper.Map<Message>(@event);
+            await _messageService.MakeMessageAsync(msg);
+        }
+    }
+}