ADR 0592 §5, §6, §9, §25 (the grants part's share by ADR 0593 §10): an object bucket and a stream that
keeps its history are created create-only with their caps and no age limit, refusing new data when full;
the owner alone writes its bucket and a module its grant names reads it; the part raises
mesh-grants.history-full once any passes 75 percent. Each engine also reads the indexer's manifest
verdicts by one key for compose-candidate.
Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL
