Allow finding large files and removing them from existing snapshots.

[ibash]

Is your feature request related to a problem? Please describe.
I don't use autorestic right now, but restic with my own scripts. I'm planning on switching over when I find the time. Something I've found very useful is to be able to automatically find large files and then use restic rewrite command to remove them from my backups.

Describe the solution you'd like
Currently this is my workflow:

1. For each snapshot run restic ls --json -l ${snapshotId} and write it to a file
2. I do some light processing to produce sizes of directories
3. Then sort by the largest files and directories
4. At this point I manually look through for directories / files that are large and I didn't want to backup anyway. I add them to a list of files to clean.
5. Then run restic rewrite all --dry-run --exclude-file clean-excludes.txt --verbose=3 to spot check
6. Then run restic rewrite all --exclude-file clean-excludes.txt --verbose=3 --forget to remove them

This does require relying on a fork of restic, but I find this very useful for my backups. Would love if something like this was available in autorestic (maybe opt-in?).

[cupcakearmy]

I think this is a bit of a niece case for an actual implementation on autorestic side.
However: you can run any restic command with autorestic with the exec command. This should enable your workflow

[ibash]

Agree, it's probably too niche!