Add Spanish and Arabic versions with a language switch

- English stays at /, Spanish at /es/ and Arabic at /ar/ (right to left)
- EN · ES · AR switch in the header and mobile menu
- Pages are written in English; the build translates them through
  src/i18n/es.json and src/i18n/ar.json, including browser-script strings
- rtl.css mirrors the layout and loads Arabic fonts on /ar/ pages
- hreflang alternates on every page and a multilingual sitemap
- scripts/i18n-extract.mjs lists strings that still need translating

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/i18n-extract.mjs

@@ -0,0 +1,23 @@
+// Lists every English string the translated pages need, and which ones a dictionary still lacks.
+//   node scripts/i18n-extract.mjs            → counts per language
+//   node scripts/i18n-extract.mjs es out.json → writes the missing Spanish strings as {english: ""}
+import { readFile, writeFile } from 'node:fs/promises';
+import { page } from '../src/layout.mjs';
+import { JS_STRINGS, mapStrings } from '../src/i18n.mjs';
+
+const pages = ['home', 'about', 'portfolio', 'consulting', 'marketing', 'business-setup', 'business-optimization', 'supply-chain', 'cybersecurity', 'education', 'fractional', 'contact', 'book', 'press'];
+const strings = new Set();
+for (const name of pages) {
+  const def = (await import(`../src/pages/${name}.mjs`)).default;
+  mapStrings(page(def, 'es'), (s) => (strings.add(s), s));
+}
+JS_STRINGS.forEach((s) => strings.add(s));
+
+const [locale, outFile] = process.argv.slice(2);
+for (const l of locale ? [locale] : ['es', 'ar']) {
+  const dict = JSON.parse(await readFile(new URL(`../src/i18n/${l}.json`, import.meta.url), 'utf8'));
+  const todo = [...strings].filter((s) => !Object.hasOwn(dict, s));
+  const unused = Object.keys(dict).filter((k) => !strings.has(k));
+  console.log(`${l}: ${strings.size} strings, ${todo.length} missing, ${unused.length} unused`);
+  if (outFile) await writeFile(outFile, JSON.stringify(Object.fromEntries(todo.map((s) => [s, ''])), null, 1) + '\n');
+}