IMAGE_NAME is now clawdie-${codename}-${ISO_VERSION}.img (e.g.
clawdie-quindecim-0.2.29.img), the version tracking zot. Drops desktop/usb/date/
commit from the filename; per-build provenance (date, clawdie-iso commit, zot
commit) lives in build-manifest.json. Removes the now-unused date/commit name
vars. Updates docs + publish-skill globs (clawdie-*) to the new format.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
