allow auth user index for multi account access

hi team, you know like in gmail or other google apps, if you are logged in to multiple accounts, you can access different one based on the index of the account

where your url becomes

https://mail.google.com/mail/u/0/
https://mail.google.com/mail/u/1/
https://mail.google.com/mail/u/2/

i wonder if we can have that on puter as well

https://puter.com/u/0/
https://puter.com/u/0/app/word-processor/ (maybe?)

google also supports using email in the url instead of the index

https://mail.google.com/mail/u/myemail@gmail.com

so we could maybe also support

https://puter.com/u/username/

this would make it easy for users to switch between personal and work account, especially as we are adding more and more work related apps