Feat: Ensure markdown formatting (#34547)

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Closes #34535

tools/scripts/ci/ensure-guide-formatting.js

@@ -0,0 +1,34 @@
+const readdirp = require('readdirp-walk');
+const { has } = require('lodash');
+const ora = require('ora');
+
+const {
+  guideRoot,
+  checkGuideFile,
+  checkFrontmatter,
+  extractLangFromFileName
+} = require('./md-testing-utils');
+
+const spinner = ora('Checking guide markdown formatting').start();
+
+const guideFrontmatterValidator = file => frontmatter => {
+  const hasLocale =
+    extractLangFromFileName(file) === 'english'
+      ? true
+      : has(frontmatter, 'localeTitle');
+  const hasTitle = has(frontmatter, 'title');
+  return hasLocale && hasTitle;
+};
+
+readdirp({ root: guideRoot })
+  .on('data', file =>
+    Promise.all([
+      checkGuideFile(file),
+      checkFrontmatter(file, { validator: guideFrontmatterValidator(file) })
+    ]).catch(err => {
+      console.error(err);
+      // eslint-disable-next-line no-process-exit
+      process.exit(1);
+    })
+  )
+  .on('end', () => spinner.stop());