界面语言切换功能，修复nav异常

hydro/script/register.js

@@ -5,6 +5,8 @@ async function run({
     uname, password, mail, uid,
 }) {
     if (!uid) uid = await system.inc('user');
+    else uid = parseInt(uid);
+    if (Number.isNaN(uid)) throw new Error('uid');
     await user.create({
         uid, uname, password, mail, regip: '127.0.0.1',
     });