refactor: 收紧角色与商户跨租户能力

src/Application/TakeoutSaaS.Application/Identity/Handlers/CreateRoleCommandHandler.cs

@@ -25,10 +25,23 @@ public sealed class CreateRoleCommandHandler(
     /// <returns>创建后的角色 DTO。</returns>
     public async Task<RoleDto> Handle(CreateRoleCommand request, CancellationToken cancellationToken)
     {
-        // 1. 获取租户上下文
-        var tenantId = request.TenantId ?? tenantProvider.GetCurrentTenantId();
+        // 1. 获取租户上下文并校验跨租户
+        var currentTenantId = tenantProvider.GetCurrentTenantId();
+        if (currentTenantId <= 0)
+        {
+            throw new BusinessException(ErrorCodes.BadRequest, "缺少租户标识");
+        }
 
-        // 2. 归一化输入并校验唯一
+        // 2. (空行后) 禁止跨租户创建
+        if (request.TenantId.HasValue && request.TenantId.Value != currentTenantId)
+        {
+            throw new BusinessException(ErrorCodes.Forbidden, "禁止跨租户创建角色");
+        }
+
+        // 3. (空行后) 使用当前租户创建角色
+        var tenantId = currentTenantId;
+
+        // 4. (空行后) 归一化输入并校验唯一
         var name = request.Name?.Trim() ?? string.Empty;
         var code = request.Code?.Trim() ?? string.Empty;
         if (string.IsNullOrWhiteSpace(name) || string.IsNullOrWhiteSpace(code))
@@ -42,7 +55,7 @@ public sealed class CreateRoleCommandHandler(
             throw new BusinessException(ErrorCodes.Conflict, "角色编码已存在");
         }
 
-        // 3. 构建角色实体
+        // 5. (空行后) 构建角色实体
         var role = new Role
         {
             TenantId = tenantId,
@@ -51,11 +64,11 @@ public sealed class CreateRoleCommandHandler(
             Description = request.Description
         };
 
-        // 4. 持久化
+        // 6. (空行后) 持久化
         await roleRepository.AddAsync(role, cancellationToken);
         await roleRepository.SaveChangesAsync(cancellationToken);
 
-        // 5. 返回 DTO
+        // 7. (空行后) 返回 DTO
         return new RoleDto
         {
             Id = role.Id,