A publication run sat silent for 8+ minutes while it downloaded ~20 GB,
with no way to tell which phase it was in or why a claim was held.
scripts/releases/progress.py logs to stderr (stdout stays the JSON steps)
with GitHub ::group::/::notice::/::error:: markers:
- every git/gh/docker command the sequencer runs, with its time and result
- discovery counts, and each claim's state with the reason (run attempt
and conclusion, draft location, abandon marker, receipt/release match)
- the plan: why each version advances, is skipped, or is held
- each step as a timed group: publish (receipt digests) and advance
- the channel advance's phases, plus per-file progress for the handoff
fetch and candidate materialize downloads (the slow part)
- the head before and after, and a top-level ::error:: on failure
