campaign introspect (--block std::process_ref and --unwired) described
the slot as "content id of a process document" — a plausible bare-string
reading the validator rejects; the required {"content_id":"..."} tagging
appeared in no introspection output (binary-only M1 fieldtest finding).
The SlotKind::ContentRef label and the open-slot hint now lead with the
tagged { content_id } shape. Deliberately narrower than the issue's
suggestion of mirroring std::strategy's { content_id } | { identity_id }
form: validate_campaign refuses an identity_id process ref
(DocFault::ProcessRefMustBeContentId) and a pinned test forbids
advertising it, so the hint states the one accepted key only (C29
honesty; correction minuted on the issue). RED-first: the extended
process_ref_describe_advertises_content_id_only assertion failed against
the old label before the fix.
closes#329
claude
73ad87b08a