The prod orchestrator only checked whether a build-image tag was *present*
before deciding to skip the build. The local UI images (bitcoin-ui, lnd-ui,
electrs-ui) COPY a built neode-ui dist, so a UI update changed the source but
left the old tag in place and the new UI never shipped.
Gate the build on a content fingerprint of the build context (sorted relative
path + length + mtime, SHA-256) recorded in a per-tag stamp under data_dir.
Rebuild whenever the fingerprint differs from the one that produced the
existing image; podman's own COPY-layer cache keeps a no-op rebuild cheap.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
3aea8c5bfa