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/Controllers/GroupController.cs

@@ -0,0 +1,43 @@
+using IM_API.Dtos;
+using IM_API.Dtos.Group;
+using IM_API.Interface.Services;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+using System.Security.Claims;
+
+namespace IM_API.Controllers
+{
+    [Authorize]
+    [Route("api/[controller]/[action]")]
+    [ApiController]
+    public class GroupController : ControllerBase
+    {
+        private readonly IGroupService _groupService;
+        private readonly ILogger<GroupController> _logger;
+        public GroupController(IGroupService groupService, ILogger<GroupController> logger)
+        {
+            _groupService = groupService;
+            _logger = logger;
+        }
+        [HttpGet]
+        [ProducesResponseType(typeof(BaseResponse<List<GroupInfoDto>>) ,StatusCodes.Status200OK)]
+        public async Task<IActionResult> GetGroups(int page = 1, int limit = 100, bool desc = false)
+        {
+            var userIdStr = User.FindFirstValue(ClaimTypes.NameIdentifier);
+            var list = await _groupService.GetGroupListAsync(int.Parse(userIdStr), page, limit, desc);
+            var res = new BaseResponse<List<GroupInfoDto>>(list);
+            return Ok(res);
+        }
+
+        [HttpPost]
+        [ProducesResponseType(typeof(BaseResponse<GroupInfoDto>), StatusCodes.Status200OK)]
+        public async Task<ActionResult> CreateGroup([FromBody]GroupCreateDto groupCreateDto)
+        {
+            var userIdStr = User.FindFirstValue(ClaimTypes.NameIdentifier);
+            var groupInfo = await _groupService.CreateGroupAsync(int.Parse(userIdStr), groupCreateDto);
+            var res = new BaseResponse<GroupInfoDto>(groupInfo);
+            return Ok(res);
+        }
+    }
+}