Add internationalization support with astro-i18next integration

- Implemented astro-i18next for multi-language support, including English, Dutch, and Italian.
- Configured default locale and language fallback settings.
- Defined routes for localized content in the configuration.
- Updated package.json and package-lock.json to include new dependencies for i18next and related plugins.

node_modules/cross-fetch/polyfill/package.json

@@ -0,0 +1,9 @@
+{
+  "name": "cross-fetch-polyfill",
+  "version": "0.0.0",
+  "main": "../dist/node-polyfill.js",
+  "browser": "../dist/browser-polyfill.js",
+  "react-native": "../dist/react-native-polyfill.js",
+  "types": "../index.d.ts",
+  "license": "MIT"
+}