Release v4.2.0

Hello all,
This release fixes a small number of bugs.

It is just a fun tech note but our releases now use 'trusted publishing' https://docs.npmjs.com/trusted-publishers

Thanks and happy browsing

bug

• Fix inconsistent filename sanitization causing broken trix file paths on desktop when track contains slash (#5540) @cmdcolin

enhancement

• Create github actions based publishing workflow using NPM trusted publishing (#5530) @cmdcolin
• Create supertrack/folder concept, browse categories/folders with faceted selector, and plugin hooks for custom track selection UI (#5515) @cmdcolin
  Done in 0.30s.