feat: 租户账单公告通知接口

src/Domain/TakeoutSaaS.Domain/Tenants/Entities/TenantAnnouncementRead.cs

@@ -0,0 +1,24 @@
+using TakeoutSaaS.Shared.Abstractions.Entities;
+
+namespace TakeoutSaaS.Domain.Tenants.Entities;
+
+/// <summary>
+/// 租户公告已读记录。
+/// </summary>
+public sealed class TenantAnnouncementRead : MultiTenantEntityBase
+{
+    /// <summary>
+    /// 公告 ID。
+    /// </summary>
+    public long AnnouncementId { get; set; }
+
+    /// <summary>
+    /// 已读用户 ID（后台账号），为空表示租户级已读。
+    /// </summary>
+    public long? UserId { get; set; }
+
+    /// <summary>
+    /// 已读时间。
+    /// </summary>
+    public DateTime ReadAt { get; set; } = DateTime.UtcNow;
+}