Allow to lock app version

Description

For every app installed via Aurora Store, there should be an option to lock that app to its currently installed version, preventing it from receiving any update via auto updates or "update all".

Additional context

Depending on the size of your app collection in Aurora Store, "update all" can prove very helpful to keep your apps updated.

However, as soon as even just one app needs to stay at its current version, "update all" becomes useless, rendering the update procedure for the remaining apps a time consuming, tedious clickfest.

The feature requested here is essential in order to make "update all" usable when some apps need to be exempted.