🐞 fix: 尝试修复无法绑定乐跑账号的问题

lib/Lepao/Mcp.js

@@ -51,7 +51,7 @@ class Mcp {
             const rows = await db.query(sql, [bind_code])
             if (!rows || rows.length === 0) return '系统出错，请稍后再试'
 
-            if (rows[0].bot_account) {
+            if (rows[0].bot_account !== null) {
                 if (rows[0].bot_account !== sender) return '该账号已被他人绑定，请联系客服解绑'
                 return '该账号您已绑定'
             }