test(PathParameter): add explicit vitest imports

fix(test): vitestのdescribe/test/expectを明示的にimport

グローバル注入に依存せず、IDE上での型エラーを解消するため
vitest から各テスト関数を明示的にimportする。

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: Himenon

src/code-templates/_shared/MethodBody/__tests__/PathParameter-test.ts

@@ -1,3 +1,5 @@
+import { describe, expect, test } from "vitest";
+
 import { TsGenerator } from "../../../../api";
 import type { CodeGenerator } from "../../../../types";
 import * as Utils from "../../utils";

src/code-templates/_shared/__tests__/utils.test.ts

@@ -1,3 +1,5 @@
+import { describe, expect, test } from "vitest";
+
 import * as Utils from "../utils";
 
 type OK = Utils.VariableElement;