albumwidget: Album art cover background

Display a blurred version of the album art cover as background. Labels
color are updated (black or white) to be visible with this new
background.

Closes: #10
4 jobs for wip/jfelder/album-cover-draw in 10 minutes and 18 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Check
passed #252525
flake8

00:01:36

 
  Build Flatpak
passed #252526
flatpak

00:08:14

 
  Deploy
passed #252527
review

00:00:27

manual #252528
allowed to fail manual
stop_review