Is there an existing issue for this?

• I have searched the existing issues

Is your feature request related to a problem? Please describe

Queued up a download for an audiobook, and it downloaded the files but didn't recognize and 'book files' as they are .opus and not mp3 or mp4.

Describe the solution you'd like

I would love for .opus to be at least recognized as a file type, and be supported for renaming and writing to for meta data.

Describe alternatives you've considered

I've manually moved the files from my download client, to my media folder, so my media server can see them and I can use them still, but readarr doesn't recognize them still and is still marked as missing.

Anything else?

I will look more into the existing file recognition structure and see if I can find references in the existing tool base to refer to a possible solution, or even suggest/make a modification or create a PR for use.

AB#3844