ReadonlycarriedThe facts this target carries — what a paste of this part would actually write.
ReadonlymissingThe facts it does not — never silently dropped; each names itself in the refusal.
ReadonlypartOptional ReadonlyrefusalWhy the part is not whole here. Present exactly when missing is non-empty, so a caller
cannot report a clean landing for a part that lost a fact. args.facts is the missing set,
comma-joined — the console's own token-list spelling on the wire.
What one part's facts did against one target.
carriedandmissingpartition the part's declared facts, so a reader never has to subtract one list from another to learn what happened.