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/i18next-http-backend/lib/utils.js

@@ -0,0 +1,44 @@
+const arr = []
+const each = arr.forEach
+const slice = arr.slice
+
+export function defaults (obj) {
+  each.call(slice.call(arguments, 1), (source) => {
+    if (source) {
+      for (const prop in source) {
+        if (obj[prop] === undefined) obj[prop] = source[prop]
+      }
+    }
+  })
+  return obj
+}
+
+export function hasXMLHttpRequest () {
+  return (typeof XMLHttpRequest === 'function' || typeof XMLHttpRequest === 'object')
+}
+
+/**
+ * Determine whether the given `maybePromise` is a Promise.
+ *
+ * @param {*} maybePromise
+ *
+ * @returns {Boolean}
+ */
+function isPromise (maybePromise) {
+  return !!maybePromise && typeof maybePromise.then === 'function'
+}
+
+/**
+ * Convert any value to a Promise than will resolve to this value.
+ *
+ * @param {*} maybePromise
+ *
+ * @returns {Promise}
+ */
+export function makePromise (maybePromise) {
+  if (isPromise(maybePromise)) {
+    return maybePromise
+  }
+
+  return Promise.resolve(maybePromise)
+}