feat: 完善手动创建租户功能，添加账单明细和支付记录

1. 手动创建租户时自动生成账单明细（LineItemsJson）
2. 账单状态为已支付时自动创建支付记录
3. 租户列表接口返回联系人信息和认证状态
4. 账单详情接口返回支付记录和解析后的账单明细
5. 管理员账号自动复用租户联系人信息

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/Domain/TakeoutSaaS.Domain/Billings/Repositories/IBillingRepository.cs

@@ -78,6 +78,14 @@ public interface IBillingRepository
     /// <param name="cancellationToken">取消标记。</param>
     /// <returns>异步操作任务。</returns>
     Task AddPaymentAsync(TenantPayment payment, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 获取账单的支付记录列表。
+    /// </summary>
+    /// <param name="billingStatementId">账单 ID。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>支付记录列表。</returns>
+    Task<IReadOnlyList<TenantPayment>> GetPaymentsByBillingIdAsync(long billingStatementId, CancellationToken cancellationToken = default);
 }
 
 /// <summary>

src/Domain/TakeoutSaaS.Domain/Tenants/Repositories/ITenantRepository.cs

@@ -4,7 +4,7 @@ using TakeoutSaaS.Domain.Tenants.Entities;
 namespace TakeoutSaaS.Domain.Tenants.Repositories;
 
 /// <summary>
-/// 租户只读仓储（AdminApi 使用）。
+/// 租户仓储（AdminApi 使用）。
 /// </summary>
 public interface ITenantRepository
 {
@@ -24,6 +24,15 @@ public interface ITenantRepository
     /// <returns>租户列表（仅返回找到的租户）。</returns>
     Task<IReadOnlyList<Tenant>> FindByIdsAsync(IReadOnlyCollection<long> tenantIds, CancellationToken cancellationToken = default);
 
+    /// <summary>
+    /// 根据编码查询租户是否存在。
+    /// </summary>
+    /// <param name="code">租户编码。</param>
+    /// <param name="excludeTenantId">排除的租户 ID。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>存在返回 true。</returns>
+    Task<bool> ExistsByCodeAsync(string code, long? excludeTenantId = null, CancellationToken cancellationToken = default);
+
     /// <summary>
     /// 获取所有租户列表（用于下拉选择器）。
     /// </summary>
@@ -61,6 +70,73 @@ public interface ITenantRepository
         int page,
         int pageSize,
         CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 在事务中批量创建租户及相关数据。
+    /// </summary>
+    /// <param name="tenant">租户实体。</param>
+    /// <param name="subscription">订阅实体。</param>
+    /// <param name="verification">认证资料实体。</param>
+    /// <param name="quotaUsages">配额使用记录列表。</param>
+    /// <param name="billing">账单实体（可选）。</param>
+    /// <param name="payment">支付记录实体（可选）。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>异步操作任务。</returns>
+    Task CreateTenantWithRelatedDataAsync(
+        Tenant tenant,
+        TenantSubscription subscription,
+        TenantVerificationProfile verification,
+        IReadOnlyList<TenantQuotaUsage> quotaUsages,
+        TenantBillingStatement? billing,
+        TenantPayment? payment,
+        CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 根据 ID 获取租户（用于更新，带跟踪）。
+    /// </summary>
+    /// <param name="tenantId">租户 ID。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>租户实体，不存在则返回 null。</returns>
+    Task<Tenant?> GetByIdForUpdateAsync(long tenantId, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 根据租户 ID 获取认证资料（用于更新，带跟踪）。
+    /// </summary>
+    /// <param name="tenantId">租户 ID。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>认证资料实体，不存在则返回 null。</returns>
+    Task<TenantVerificationProfile?> GetVerificationForUpdateAsync(long tenantId, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 新增租户。
+    /// </summary>
+    /// <param name="tenant">租户实体。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>异步操作任务。</returns>
+    Task AddAsync(Tenant tenant, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 新增租户订阅。
+    /// </summary>
+    /// <param name="subscription">订阅实体。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>异步操作任务。</returns>
+    Task AddSubscriptionAsync(TenantSubscription subscription, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 新增租户认证资料。
+    /// </summary>
+    /// <param name="verification">认证资料实体。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>异步操作任务。</returns>
+    Task AddVerificationAsync(TenantVerificationProfile verification, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 保存仓储变更。
+    /// </summary>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>异步操作任务。</returns>
+    Task SaveChangesAsync(CancellationToken cancellationToken = default);
 }
 
 /// <summary>