Is your feature request related to a problem? Please describe.
So I've been using Foobar to write Replaygain onto my tracks, but the problem with that is it doesn't overwrite the original file, which is tedious to manually do when you have a large library.

Describe the solution you'd like
I want Fre:ac to scan tracks and peaks and write Replaygain volume changes on conversion.

Describe alternatives you've considered
Foobar is the only app I use that scans Replaygain and writes to it, but like I said, it doesn't support overwriting the input file.

Additional context
Add any other context or screenshots about the feature request here.