feat: 租户账单公告通知接口

src/Application/TakeoutSaaS.Application/App/Tenants/Handlers/GetTenantBillQueryHandler.cs

@@ -0,0 +1,19 @@
+using MediatR;
+using TakeoutSaaS.Application.App.Tenants.Dto;
+using TakeoutSaaS.Application.App.Tenants.Queries;
+using TakeoutSaaS.Domain.Tenants.Repositories;
+
+namespace TakeoutSaaS.Application.App.Tenants.Handlers;
+
+/// <summary>
+/// 账单详情查询处理器。
+/// </summary>
+public sealed class GetTenantBillQueryHandler(ITenantBillingRepository billingRepository)
+    : IRequestHandler<GetTenantBillQuery, TenantBillingDto?>
+{
+    public async Task<TenantBillingDto?> Handle(GetTenantBillQuery request, CancellationToken cancellationToken)
+    {
+        var bill = await billingRepository.FindByIdAsync(request.TenantId, request.BillingId, cancellationToken);
+        return bill?.ToDto();
+    }
+}