Misc fixes

[gp-slick-coder]

fixes

• error handling on file download
• copyright null fix
• is_multiple fix (on track download)
• include vscode debug script, cleanup

notes

to reproduce the copyright fix, you can use this track

• https://open.qobuz.com/track/652159

[vitiko98]

Thanks a lot!

I'm bumping the version and uploading to PyPi in the upcoming days...