refactor: share common intro creation code (#61814)

tools/challenge-helper-scripts/helpers/create-intro.ts

@@ -0,0 +1,36 @@
+import path from 'node:path';
+import fs from 'node:fs/promises';
+
+function introTemplate(
+  superBlock: string,
+  block: string,
+  title: string
+): string {
+  return `---
+title: Introduction to the ${title}
+block: ${block}
+superBlock: ${superBlock}
+---
+
+## Introduction to the ${title}
+
+This page is for the ${title}
+`;
+}
+
+export async function createIntroMD(
+  superBlock: string,
+  block: string,
+  title: string
+) {
+  const dirPath = path.resolve(
+    __dirname,
+    `../../../client/src/pages/learn/${superBlock}/${block}/`
+  );
+  await fs.mkdir(dirPath, { recursive: true });
+
+  const filePath = path.resolve(dirPath, 'index.md');
+  await fs.writeFile(filePath, introTemplate(superBlock, block, title), {
+    encoding: 'utf8'
+  });
+}