App preview in app switcher (Low priority)

**Is your feature request related to a problem? Please describe.**
I could not find any related problem.

**Describe the solution you'd like**
I would like to see the preview of KeePassDX in the app switcher while disallowing screenshots.

**Describe alternatives you've considered**
As I know that `FLAG_SECURE` is used in KeePassDX for this. I am not sure if this is even possible in Android but I would appreciate if at least someone is able to create a toggle to allow screenshots so that the thumbnail is visible in the app switcher.

**Additional context**
Android 12 (Google Pixel 6)
There are still apps where credential fields are not recognized by Android thus users need to switch to KeePass to copy the
username and password manually.

_Note: App preview appears when you open the app switcher and is visible until you switch to another app or homescreen. When you then open the app switcher again there will be no preview for KeePass._

**Screenshot of showcasing the issue:**

Start by tracing KeePassDX’s use of Android FLAG_SECURE and the app-switcher behavior described for Android 12. Check whether a user-controlled screenshot toggle can provide the requested preview while preserving the intended security behavior. Done means the feasibility is established and the requested behavior is implemented or clearly documented as unsupported.

Written by the indexing model from the issue text.