chore: 后端首次基线提交

运行必须源码：app/(controller/model/service/middleware/lib/utils/validate/router)、config/、database/(migrations/seeders/sql)、启动脚本、app/public/templates 模板。
已忽略运行非必须：node_modules/、logs/、run/、app/public 运行时上传数据、.env*、构建/缓存产物。

database/seeders/002-seed-admin.js

@@ -0,0 +1,36 @@
+'use strict';
+
+module.exports = {
+  up: async (queryInterface, Sequelize) => {
+    const now = new Date();
+    await queryInterface.bulkInsert('accounts', [
+      {
+        role: 'admin',
+        name_cn: '系统管理员',
+        name_en: 'Administrator',
+        gender: null,
+        phone: null,
+        email: 'admin@competition.com',
+        id_number: '000000000000000000',
+        password: '$2b$10$Nc6PCJItIwuOzpM22dTiAezB.jZMI8mzkCbg3oRZkAWx.QaI4co9.',
+        salt: '$2b$10$Nc6PCJItIwuOzpM22dTiAe',
+        position: '系统管理员',
+        major: null,
+        country: '中国',
+        region: null,
+        organization_cn: '赛事组委会',
+        organization_en: 'Competition Committee',
+        activated: 1,
+        score: null,
+        created_at: now,
+        updated_at: now,
+      },
+    ], {});
+  },
+
+  down: async (queryInterface, Sequelize) => {
+    await queryInterface.bulkDelete('accounts', {
+      id_number: '000000000000000000',
+    }, {});
+  },
+};