docs: 完善AdminApi控制器注释和代码规范

src/Api/TakeoutSaaS.AdminApi/Controllers/TenantNotificationsController.cs

@@ -21,6 +21,7 @@ public sealed class TenantNotificationsController(IMediator mediator) : BaseApiC
     /// <summary>
     /// 分页查询通知。
     /// </summary>
+    /// <returns>租户通知分页结果。</returns>
     [HttpGet]
     [PermissionAuthorize("tenant-notification:read")]
     [ProducesResponseType(typeof(ApiResponse<PagedResult<TenantNotificationDto>>), StatusCodes.Status200OK)]
@@ -39,6 +40,7 @@ public sealed class TenantNotificationsController(IMediator mediator) : BaseApiC
     /// <summary>
     /// 标记通知已读。
     /// </summary>
+    /// <returns>标记已读后的通知信息。</returns>
     [HttpPost("{notificationId:long}/read")]
     [PermissionAuthorize("tenant-notification:update")]
     [ProducesResponseType(typeof(ApiResponse<TenantNotificationDto>), StatusCodes.Status200OK)]