chore: add five-language README sync gate

package.json

@@ -51,6 +51,7 @@
     "typecheck": "tsc --noEmit",
     "typecheck:ci": "tsc --noEmit --pretty false",
     "test": "vitest run",
+    "check:readmes": "node scripts/check-readme-sync.mjs",
     "check:kit": "pwsh -File scripts/verify-kit.ps1",
     "verify:artifacts": "node scripts/verify-artifacts.mjs",
     "verify:self-contained": "pnpm run build && node dist/dsh-plugin-dev.js verify",

scripts/check-readme-sync.mjs

@@ -0,0 +1,91 @@
+#!/usr/bin/env node
+// Five-language README sync gate: the English file is the source of truth.
+// Every translation must carry the same `## ` section headings in the same
+// order and the same configuration-table keys, so a config change cannot
+// ship without its translations.
+import { readFileSync, existsSync } from 'node:fs'
+import path from 'node:path'
+import { fileURLToPath } from 'node:url'
+
+const root = path.dirname(path.dirname(fileURLToPath(import.meta.url)))
+const LANGUAGES = [
+  ['README.md', 'en'],
+  ['README.zh.md', 'zh'],
+  ['README.es.md', 'es'],
+  ['README.pt.md', 'pt'],
+  ['README.hi.md', 'hi'],
+]
+
+const headingsOf = (text) => text.split(/\r?\n/u)
+  .map(line => /^##\s+(.+)$/u.exec(line)?.[1]?.trim())
+  .filter((heading) => heading !== undefined)
+
+// Configuration-table keys: the first cell of every row under the
+// "Configuration" section (until the next `## ` heading).
+const configKeysOf = (text) => {
+  const lines = text.split(/\r?\n/u)
+  const start = lines.findIndex(line => /^##\s+Configuration\s*$/u.test(line))
+  if (start === -1) return []
+  const end = lines.findIndex((line, index) => index > start && line.startsWith('## '))
+  const section = lines.slice(start, end === -1 ? undefined : end)
+  const keys = []
+  let headerSkipped = false
+  for (const line of section) {
+    if (!line.startsWith('|')) continue
+    if (!headerSkipped) { headerSkipped = true; continue }
+    const cells = line.split('|').map(cell => cell.trim())
+    if (cells.length < 2) continue
+    const key = cells[1]
+    if (key === '' || key === 'Key') continue
+    if (/^-+$/u.test(key)) continue
+    keys.push(key)
+  }
+  return keys
+}
+
+const failures = []
+const reference = LANGUAGES[0]
+if (reference === undefined) process.exit(1)
+const refPath = path.join(root, reference[0])
+if (!existsSync(refPath)) {
+  console.error(`${reference[0]} is missing`)
+  process.exit(1)
+}
+const refText = readFileSync(refPath, 'utf8')
+const refHeadings = headingsOf(refText)
+const refKeys = configKeysOf(refText)
+
+for (const [file, label] of LANGUAGES.slice(1)) {
+  const filePath = path.join(root, file)
+  if (!existsSync(filePath)) {
+    failures.push(`${file}: missing (${label})`)
+    continue
+  }
+  const text = readFileSync(filePath, 'utf8')
+  const headings = headingsOf(text)
+  for (let index = 0; index < refHeadings.length; index++) {
+    if (headings[index] !== refHeadings[index]) {
+      failures.push(`${file}: heading ${index + 1} is ${JSON.stringify(headings[index])}, expected ${JSON.stringify(refHeadings[index])}`)
+    }
+  }
+  if (headings.length !== refHeadings.length) {
+    failures.push(`${file}: ${headings.length} headings, expected ${refHeadings.length}`)
+  }
+  const keys = configKeysOf(text)
+  if (keys.length !== refKeys.length) {
+    failures.push(`${file}: ${keys.length} config keys, expected ${refKeys.length}`)
+    continue
+  }
+  for (let index = 0; index < refKeys.length; index++) {
+    if (keys[index] !== refKeys[index]) {
+      failures.push(`${file}: config key ${index + 1} is ${JSON.stringify(keys[index])}, expected ${JSON.stringify(refKeys[index])}`)
+    }
+  }
+}
+
+if (failures.length > 0) {
+  console.error('readme-sync failed:')
+  for (const failure of failures) console.error(`  - ${failure}`)
+  process.exit(1)
+}
+console.log(`readme-sync: all ${LANGUAGES.length} READMEs share section structure and config keys`)