Add i18n for side tool bar tooltips (#207)

* Add npm dep

* Add i18n for side bar tooltips

src/i18n.ts

@@ -0,0 +1,27 @@
+import { createI18n } from "vue-i18n";
+
+const messages = {
+  en: {
+    sideToolBar: {
+      settings: "Settings",
+      themeToggle: "Toggle Theme",
+      queue: "Queue",
+    },
+  },
+  zh: {
+    sideToolBar: {
+      settings: "设置",
+      themeToggle: "主题切换",
+      queue: "队列",
+    },
+  },
+  // TODO: Add more languages
+};
+
+export const i18n = createI18n({
+  // Must set `false`, as Vue I18n Legacy API is for Vue 2
+  legacy: false,
+  locale: navigator.language.split("-")[0] || "en",
+  fallbackLocale: "en",
+  messages,
+});