fix(test): add missing Type field in BenchmarkE2EBasicAuth

The AuthConfig struct requires Type="basic" for NewBasicAuth to
validate successfully. Without this field, the benchmark fails with
"unsupported auth type: ".

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

internal/integration/e2e_bench_test.go

@@ -1449,6 +1449,7 @@ func BenchmarkE2EBasicAuth(b *testing.B) {
 	// 创建 Basic Auth 中间件（使用 bcrypt 哈希）
 	bcryptPassword, _ := security.HashPassword("testpass", security.HashBcrypt)
 	auth, err := security.NewBasicAuth(&config.AuthConfig{
+		Type:       "basic",
 		RequireTLS: false,
 		Users: []config.User{
 			{Name: "admin", Password: bcryptPassword},