refactor: 将 Permission 和 MenuDefinition 改为系统级实体

- Permission 和 MenuDefinition 改为继承 AuditableEntityBase（移除 TenantId）
- 添加 PortalType 枚举区分平台端/租户端
- Repository 使用 IgnoreQueryFilters() 查询系统级数据
- 更新所有相关 Handler 和 DTO，移除 TenantId 引用
- 与 AdminApi 保持一致的设计

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

src/Infrastructure/TakeoutSaaS.Infrastructure/Identity/Repositories/EfMenuRepository.cs

@@ -1,5 +1,6 @@
 using Microsoft.EntityFrameworkCore;
 using TakeoutSaaS.Domain.Identity.Entities;
+using TakeoutSaaS.Domain.Identity.Enums;
 using TakeoutSaaS.Domain.Identity.Repositories;
 using TakeoutSaaS.Infrastructure.Identity.Persistence;
 
@@ -11,28 +12,28 @@ namespace TakeoutSaaS.Infrastructure.Identity.Repositories;
 public sealed class EfMenuRepository(IdentityDbContext dbContext) : IMenuRepository
 {
     /// <inheritdoc />
-    public async Task<IReadOnlyList<MenuDefinition>> GetByTenantAsync(long tenantId, CancellationToken cancellationToken = default)
+    public async Task<IReadOnlyList<MenuDefinition>> GetByPortalAsync(PortalType portal, CancellationToken cancellationToken = default)
     {
-        // 1. 仅返回该租户的菜单，无回退逻辑
-        var tenantMenus = await dbContext.MenuDefinitions
+        // 1. 按门户类型查询菜单（忽略租户过滤器）
+        var menus = await dbContext.MenuDefinitions
+            .IgnoreQueryFilters()
             .AsNoTracking()
-            .Where(x => x.TenantId == tenantId && x.DeletedAt == null)
+            .Where(x => x.Portal == portal && x.DeletedAt == null)
             .OrderBy(x => x.ParentId)
             .ThenBy(x => x.SortOrder)
             .ToListAsync(cancellationToken);
 
-        return tenantMenus;
+        return menus;
     }
 
     /// <inheritdoc />
-    public async Task<MenuDefinition?> FindByIdAsync(long id, long tenantId, CancellationToken cancellationToken = default)
+    public async Task<MenuDefinition?> FindByIdAsync(long id, CancellationToken cancellationToken = default)
     {
-        // 1. 仅查询该租户的菜单，无回退逻辑
+        // 1. 按 ID 查询菜单（忽略租户过滤器）
         return await dbContext.MenuDefinitions
+            .IgnoreQueryFilters()
             .AsNoTracking()
-            .FirstOrDefaultAsync(
-                x => x.Id == id && x.TenantId == tenantId && x.DeletedAt == null,
-                cancellationToken);
+            .FirstOrDefaultAsync(x => x.Id == id && x.DeletedAt == null, cancellationToken);
     }
 
     /// <inheritdoc />
@@ -49,11 +50,12 @@ public sealed class EfMenuRepository(IdentityDbContext dbContext) : IMenuReposit
     }
 
     /// <inheritdoc />
-    public async Task DeleteAsync(long id, long tenantId, CancellationToken cancellationToken = default)
+    public async Task DeleteAsync(long id, CancellationToken cancellationToken = default)
     {
-        // 1. 查询目标
+        // 1. 查询目标（忽略租户过滤器）
         var entity = await dbContext.MenuDefinitions
-            .FirstOrDefaultAsync(x => x.Id == id && x.TenantId == tenantId, cancellationToken);
+            .IgnoreQueryFilters()
+            .FirstOrDefaultAsync(x => x.Id == id, cancellationToken);
 
         // 2. 存在则删除
         if (entity is not null)