Add link to GitHub repository

Author: wxh06

src/components/PageHeader.vue

@@ -1,14 +1,20 @@
 <script setup lang="ts">
 import { RouterLink } from "vue-router";
 import Menubar from "primevue/menubar";
+import type { MenuItem } from "primevue/menuitem";
 import UserInput from "./UserInput.vue";
 
-const items = [
+const items: MenuItem[] = [
   {
     label: "比赛",
     icon: "pi pi-chart-bar",
     route: "/",
   },
+  {
+    label: "GitHub",
+    icon: "pi pi-github",
+    url: "https://github.com/wxh06/lgtracker",
+  },
 ];
 </script>