build: configure Cloudflare Pages deployment

- Add wrangler CLI and workerd runtime as dev dependencies
- Configure nitro prerender with autoSubfolderIndex disabled for Pages
- Add Turnstile validation endpoint for server-side CAPTCHA verification
- Add baseline-browser-mapping for browser compatibility

i18n.config.ts

@@ -1,15 +1,4 @@
 export default defineI18nConfig(() => ({
   legacy: false,
   locale: 'en',
-  messages: {
-    en: {
-      welcome: 'Welcome',
-    },
-    fr: {
-      welcome: 'Bienvenue',
-    },
-    lfn: {
-      welcome: 'Bonveni',
-    },
-  },
 }));