feat: 列表接口分页排序与验证

src/Application/TakeoutSaaS.Application/App/Merchants/Handlers/SearchMerchantsQueryHandler.cs

@@ -2,6 +2,7 @@ using MediatR;
 using TakeoutSaaS.Application.App.Merchants.Dto;
 using TakeoutSaaS.Application.App.Merchants.Queries;
 using TakeoutSaaS.Domain.Merchants.Repositories;
+using TakeoutSaaS.Shared.Abstractions.Results;
 using TakeoutSaaS.Shared.Abstractions.Tenancy;
 
 namespace TakeoutSaaS.Application.App.Merchants.Handlers;
@@ -12,13 +13,13 @@ namespace TakeoutSaaS.Application.App.Merchants.Handlers;
 public sealed class SearchMerchantsQueryHandler(
     IMerchantRepository merchantRepository,
     ITenantProvider tenantProvider)
-    : IRequestHandler<SearchMerchantsQuery, IReadOnlyList<MerchantDto>>
+    : IRequestHandler<SearchMerchantsQuery, PagedResult<MerchantDto>>
 {
     private readonly IMerchantRepository _merchantRepository = merchantRepository;
     private readonly ITenantProvider _tenantProvider = tenantProvider;
 
     /// <inheritdoc />
-    public async Task<IReadOnlyList<MerchantDto>> Handle(SearchMerchantsQuery request, CancellationToken cancellationToken)
+    public async Task<PagedResult<MerchantDto>> Handle(SearchMerchantsQuery request, CancellationToken cancellationToken)
     {
         var tenantId = _tenantProvider.GetCurrentTenantId();
         var merchants = await _merchantRepository.SearchAsync(tenantId, request.Status, cancellationToken);
@@ -29,7 +30,7 @@ public sealed class SearchMerchantsQueryHandler(
             .Take(request.PageSize)
             .ToList();
 
-        return paged.Select(merchant => new MerchantDto
+        var items = paged.Select(merchant => new MerchantDto
         {
             Id = merchant.Id,
             TenantId = merchant.TenantId,
@@ -43,6 +44,8 @@ public sealed class SearchMerchantsQueryHandler(
             JoinedAt = merchant.JoinedAt,
             CreatedAt = merchant.CreatedAt
         }).ToList();
+
+        return new PagedResult<MerchantDto>(items, request.Page, request.PageSize, merchants.Count);
     }
 
     private static IOrderedEnumerable<Domain.Merchants.Entities.Merchant> ApplySorting(

src/Application/TakeoutSaaS.Application/App/Merchants/Queries/SearchMerchantsQuery.cs

@@ -1,13 +1,14 @@
 using MediatR;
 using TakeoutSaaS.Application.App.Merchants.Dto;
 using TakeoutSaaS.Domain.Merchants.Enums;
+using TakeoutSaaS.Shared.Abstractions.Results;
 
 namespace TakeoutSaaS.Application.App.Merchants.Queries;
 
 /// <summary>
 /// 搜索商户列表。
 /// </summary>
-public sealed class SearchMerchantsQuery : IRequest<IReadOnlyList<MerchantDto>>
+public sealed class SearchMerchantsQuery : IRequest<PagedResult<MerchantDto>>
 {
     /// <summary>
     /// 按状态过滤。