Backup/restore functionality

[lunalucadou]

I've completed all of the puzzles in easy and medium, and most of the puzzles in hard. When I swapped devices, I expected that progress to be ported via the data transfer process, but it was not, and to make matters worse, ADB backup has been deprecated since Android 12, so the method I previously used to migrate my progress is entirely unusable on my Pixel 8a running Android 14.

Since there is no longer any manual way to port progress between devices, it would be ideal if the app included the database in the Android auto-backup config, Google Play Games sync, or a manual backup/restore feature.