A decoder keeps the last of two equal keys without a word, so a merge
of two branches that each add a field to a manifest loses one side
silently; the indexer's judge reads the same bytes. Rows: a top-level
field and a field inside an artifact, each named by its path.
Claude-Session: https://claude.ai/code/session_01JG73KJNrH5EgFXMKKYSrig