feat: 扩展领域模型与配置

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

@@ -0,0 +1,50 @@
+using TakeoutSaaS.Domain.Tenants.Enums;
+using TakeoutSaaS.Shared.Abstractions.Entities;
+
+namespace TakeoutSaaS.Domain.Tenants.Entities;
+
+/// <summary>
+/// 租户账单，用于呈现周期性收费。
+/// </summary>
+public sealed class TenantBillingStatement : MultiTenantEntityBase
+{
+    /// <summary>
+    /// 账单编号，供对账查询。
+    /// </summary>
+    public string StatementNo { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 账单周期开始时间。
+    /// </summary>
+    public DateTime PeriodStart { get; set; }
+
+    /// <summary>
+    /// 账单周期结束时间。
+    /// </summary>
+    public DateTime PeriodEnd { get; set; }
+
+    /// <summary>
+    /// 应付金额。
+    /// </summary>
+    public decimal AmountDue { get; set; }
+
+    /// <summary>
+    /// 实付金额。
+    /// </summary>
+    public decimal AmountPaid { get; set; }
+
+    /// <summary>
+    /// 当前付款状态。
+    /// </summary>
+    public TenantBillingStatus Status { get; set; } = TenantBillingStatus.Pending;
+
+    /// <summary>
+    /// 到期日。
+    /// </summary>
+    public DateTime DueDate { get; set; }
+
+    /// <summary>
+    /// 账单明细 JSON，记录各项费用。
+    /// </summary>
+    public string? LineItemsJson { get; set; }
+}