ADD: Settings store

src/stores/settings.ts

+import { defineStore } from 'pinia'
+
+export const useSettingsStore = defineStore('settings', () => {
+  const language: Ref<string> = ref('')
+  function setLanguage(lang_value: string) {
+    language.value = lang_value
+  }
+  return { language, setLanguage }
+}, { persist: true })