Request: Implement security PIN re-prompt when switching between apps

[win-open]

I've noticed that when the Mauth Authenticator app runs in the background and I switch between apps, it doesn't re-prompt me to enter the security PIN when I return to the app. Instead, it directly displays the tokens.

I think it would be a great security feature to re-prompt the user to enter the security PIN every time they switch between apps and land on the Mauth Authenticator app, not just on app startup. This would add an extra layer of protection against unauthorized access to the tokens.

@X1nto Could you please consider implementing this feature? It would be a great enhancement to the app's security and usability.

Steps to reproduce:

1. Open Mauth Authenticator app and set up a security PIN.
2. Switch to another app and then return to Mauth Authenticator.
3. Observe that the app doesn't re-prompt for the security PIN and directly displays the tokens.

Expected behavior: The app should re-prompt the user to enter the security PIN every time they switch between apps and land on the Mauth Authenticator app.