Script Menu Issue?
The other day I dumped a couple of new AppleScript files into [home]/Library/Music/Scripts/ to make sure they ran OK from there and was surprised that the Music app did not recognize them and that they did not display in its Script menu.
Re-launched Music. Nothing.
Restarted the machine. Nothing.
Now, I am using the latest beta of Music on the latest beta of macOS 10.15.4, so maybe it's a beta thing. However, I've seen this behavior in the past and it generally is resolved by restarting Music. But not this time.
Anyway, if you are seeing the same problem, try installing the script files in the local Library location: [startupdisk]/Library/Music/Scripts/. That worked as expected for me. (I haven't tested this with scripts for the TV app.)