feat: add sammyette.party to cool-sites
feat: add mattwidmann.net to cool-sites
fix: only check error code in conditional
tweak: error message wording
refactor: use posix flags for tar
tweak: generate archive as temporary file
tweak: get sourcehut username from environment var
tweak: use conditional to publish site
tweak: add dependency check logic to build script
feat: add invisible-island.net to cool-sites
tweak: update project language and description
tweak: change blog directory structure
chore: update music in about-me