v3.0.4 — bib :latest, single-tag patch

Single fix: bootc-image-builder pin must be :latest because upstream
doesn't ship semver. v3.0.3 publish-images failed building the bib
catalog image; carmine main hit the same on bootc-boot-smoke.

Also captures the pyinfra-smoke-on-big-images known issue (vfs
storage driver + 3GB carmine:stable = disk full) as a v3.1
follow-up — not blocking; affects only consumers running smoke
against the full instance image rather than a slim target.