Insecure login on LAN

[ManuXD32]

Describe the bug
If you login on a machine, the account stays opened, so if you access the webui from another machine you can get to the web page without loging in again

To Reproduce

1. Setup backrest on a server with port 0.0.0.0
2. Login from machine 2
3. Try to login from machine 3

Expected behavior
Ask for login on different machines

Screenshots
If applicable, add screenshots to help explain your problem.

Platform Info

• OS and Architecture Ubuntu server 24.0.1
• Backrest Version 1.6.1

[garethgeorge]

Backrest supports password authentication to address multiuser installs where other users of the system need to be restricted from accessing the UI.

Interestingly, if running multiple installs under different user accounts I think one would also have problems with each install trying to bind to port 8989. For now, on a multi user system backrest should always be used with authentication enabled and only on a single user account.