fix: a shell opens without the password and code again while the user's last use of a shell is within web.shell_auth_timeout minutes.

debian-package/src/usr/share/doc/vpn-router/vpn-router.json.example

@@ -63,7 +63,8 @@
     "trusted_proxies": [],
     "status_content": "basic",
     "shell": false,
-    "shell_idle_minutes": 15
+    "shell_idle_minutes": 15,
+    "shell_auth_timeout": 15
   },
   "ssh": {
     "ldap_login": false