Adopt package & clean up

Small changes, repo was in pretty good shape before orphaned.

• updated maintainer & changelog
• updated d/copyright
• updated standard version to 4.7.2
• added recommends to d/control, as suggested here
• added upstream/metadata
• added salsa ci config
• added lintian override as hyprland-share-picker does not contain any documentation

Note: As I do not have permission to change repo settings, I would be grateful if you could add debian/salsa-ci.yml as CI control file.