Add audio metadata to "best" format

[MarkimusZer0]

bug description I believe it's a bug, but downloading files (at least from YouTube) with the audio format set to best will cause them to come out without metadata

reproduction steps steps to reproduce the behavior:

1. Have audio format set to best
2. Download any video as an audio
3. See error

videos

https://github.com/wukko/cobalt/assets/73902340/c6452348-cf58-484b-b9c3-3279bb2a392c

https://github.com/wukko/cobalt/assets/73902340/36f85822-f38a-40f0-ab7f-71d4152da07f

platform

• OS: Android 11
• Chrome
• Cobalt V.7.11

additional context add any other context about the problem here.

[wukko]

this is expected behaviour because file is not modified by the processing server in any way. but i will convert this into a feature request :D