Quality upgrade scan

Check every album in your library against Qobuz and find the ones available at higher quality than your copy. You review the list and choose what to re-rip; originals are backed up before anything is replaced, and the upgrade is skipped if it would drop bonus tracks you have.

This is opt-in: normal downloads never touch files you already have. Backups are kept for 7 days and then cleaned up on next startup.