feat: add persist feature for frontend

frontend/src/stores/i18n.ts

@@ -1,9 +1,12 @@
-import { ref, computed } from 'vue'
 import { defineStore } from 'pinia'
 import { Language } from '@/utils/i18n'
 
+interface LanguageState {
+  language: Language
+}
+
 export const useLanguageStore = defineStore('language', {
-  state: () => ({
+  state: (): LanguageState => ({
     language: Language.English
   }),
 
@@ -23,4 +26,10 @@ export const useLanguageStore = defineStore('language', {
       this.changeLanguage(Language.SimplifiedChinese);
     },
   },
+
+  persist: {
+    key: 'ccn-i18n',
+    storage: localStorage,
+    pick: ['language'],
+  },
 })

frontend/src/stores/token.ts

@@ -0,0 +1,30 @@
+import { defineStore } from 'pinia'
+
+interface TokenState {
+    token: string | null
+}
+
+export const useTokenStore = defineStore('token', {
+  state: (): TokenState => ({
+    token: null,
+  }),
+
+  getters: {
+    isLoggedIn: (state) => typeof state.token === 'string',
+  },
+
+  actions: {
+    login(token: string) {
+        this.token = token;
+    },
+    logout() {
+        this.token = null;
+    },
+  },
+
+  persist: {
+    key: 'ccn-token',
+    storage: localStorage,
+    pick: ['token'],
+  },
+})