Refactor i18n settings and improve language load handling

This update separates the creation of i18n settings into its own function (@kit/i18n) and enhances the handling of language and namespace loading in i18n.client. It tracks loaded languages and namespaces, and prevents rendering if none are loaded or after a maximum number of iterations. The usage of Suspense has also been modified in root-providers to employ a null fallback.

packages/i18n/src/create-i18n-settings.ts

@@ -0,0 +1,33 @@
+/**
+ * Get i18n settings for i18next.
+ * @param languages
+ * @param language
+ * @param namespaces
+ */
+export function createI18nSettings({
+  languages,
+  language,
+  namespaces,
+}: {
+  languages: string[];
+  language: string;
+  namespaces?: string | string[];
+}) {
+  const lng = language;
+  const ns = namespaces;
+
+  return {
+    supportedLngs: languages,
+    fallbackLng: languages[0],
+    detection: undefined,
+    lng,
+    load: 'languageOnly',
+    preload: false,
+    lowerCaseLng: true,
+    fallbackNS: ns,
+    ns,
+    react: {
+      useSuspense: true,
+    },
+  };
+}