1.11: add setting to start "in background"?

[lkraav]

I've configured my laptop 2FA as the starred cover code item. Getting this code is by far the most often occurring use case.

After being reaped by oom-killer, or phone boot, if SailOTP could somehow be configured to

• not display UI by default
• stay in task switcher, and display cover code

Would help UX convenience / speed of access for that one favorite code a lot.