feat: 添加用户权限洞察查询与示例

src/Domain/TakeoutSaaS.Domain/Identity/Repositories/IIdentityUserRepository.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
 using TakeoutSaaS.Domain.Identity.Entities;
@@ -19,4 +20,12 @@ public interface IIdentityUserRepository
     /// 根据 ID 获取后台用户。
     /// </summary>
     Task<IdentityUser?> FindByIdAsync(long userId, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 按租户与关键字查询后台用户列表（仅读）。
+    /// </summary>
+    /// <param name="tenantId">租户 ID。</param>
+    /// <param name="keyword">可选关键字（账号/名称）。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    Task<IReadOnlyList<IdentityUser>> SearchAsync(long tenantId, string? keyword, CancellationToken cancellationToken = default);
 }