[Feature] Per-user storage locations (separate directories / drives / partitions per user)

I have searched the existing feature requests, both open and closed, to make sure this is not a duplicate request. • Yes The feature Feature request Please add official support for assigning each user their own storage location, so different users' uploaded libraries can live in different directories, drives, partitions or storage devices. A concrete example of what I want to do: I have a single large HDD split into one partition per user (for example /mnt/alice, /mnt/bob, /mnt/carol), and I want each user's Immich library to be stored on their own partition. I want to be able to do this natively in Immich, without bind-mount or symlink hacks. Problem All users' uploads currently live under a single UPLOAD_LOCATION, with a per-user subfolder inside it. For a shared instance (family, friends, small team) there is no supported way to put one user's library on a different disk or partition from another's. Why per-user partitions or d…