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/@babel/runtime/regenerator/index.js

@@ -0,0 +1,15 @@
+// TODO(Babel 8): Remove this file.
+
+var runtime = require("../helpers/regeneratorRuntime")();
+module.exports = runtime;
+
+// Copied from https://github.com/facebook/regenerator/blob/main/packages/runtime/runtime.js#L736=
+try {
+  regeneratorRuntime = runtime;
+} catch (accidentalStrictMode) {
+  if (typeof globalThis === "object") {
+    globalThis.regeneratorRuntime = runtime;
+  } else {
+    Function("r", "regeneratorRuntime = r")(runtime);
+  }
+}