fix(server): 赛事包导出传入项目名，修复 GET /api/export/project.zip 恒 500

web/src/admin/pages/LoginPage.vue

@@ -41,7 +41,7 @@ function asGuest(): void {
     <div class="mx-card login-card">
       <div class="mx-card-body">
         <div class="login-brand">
-          <span class="mx-logo-icon"><MxIcon name="standings" :size="20" /></span>
+          <img class="app-icon" src="/scoreboard.png" alt="" width="36" height="36" />
           <div>
             <h1>积分榜管理面板</h1>
             <p>2026 职工运动会 · 成绩录入与实时积分</p>