For your second point, you might want to have a look at Perkeep: https://perkeep.org/
It supports the kind of queries you are after, but it’s a bit of a passion project and development is slow. What’s already there works well though.
It supports the kind of queries you are after, but it’s a bit of a passion project and development is slow. What’s already there works well though.
I hope it can be adjusted to my needs: I expect I'm going to have to find solutions for tracking files' sources, for snapshots, and for remote/removable storage, in addition to all the UI work.