fix: 修复 issue-template 测试误删 .github/workflows 目录

afterEach 清理时 rmSync 误删了整个 .github/ 目录（含 workflows），
改为只删测试创建的 ISSUE_TEMPLATE 子目录。

Co-Authored-By: glm-5-turbo <zai-org@claude-code-best.win>

src/commands/issue/__tests__/issue-template.test.ts

@@ -202,9 +202,9 @@ function createTemplateInCwd(files: Record<string, string>): string {
   for (const [name, content] of Object.entries(files)) {
     writeFileSync(join(templateDir, name), content)
   }
-  // Track the .github dir for cleanup (remove whole .github if it didn't exist)
-  const githubDir = join(realCwd, '.github')
-  createdTemplatePath = githubDir
+  // Track the ISSUE_TEMPLATE dir for cleanup — never delete the whole .github/
+  // as it may contain workflows, settings, or other project config.
+  createdTemplatePath = templateDir
   return templateDir
 }