You can have a look at this module idle Session Time out , I haven’t tried it in PWA. You can give it a try.
Good Luck !!
Have a look at the Session Timeout widget in the appstore.
if you have your app deployed on cloud or running locally, you can add the custom environment variable in the runtime customizations.
SessionTimeout : 6000 (1 minute)
see below screenshot for local
Also you can use the IdleSessionTimeOut module… idle time out