fix(migrate): improve

Author: std-microblock

migrate/migrate-bot.js

@@ -215,7 +215,7 @@ async function writeMDXFile(filePath, content, title) {
   const dir = path.dirname(filePath);
   await fs.mkdir(dir, { recursive: true });
   const frontmatter = `---
-title: "${title}"
+title: ${JSON.stringify(title)}
 description: Auto‑generated from cppreference
 ---\n\n`;
   await fs.writeFile(filePath, frontmatter + content, "utf8");