A resource attached in a save now ignores any sponsor recorded for it
before it was removed: the caller must be able to sponsor it and confirm.
YAML import prunes the sponsors of resources it drops, for agents and
workflow graphs. Sponsor details, with the resources' names, go only to
people who may edit the agent. The workflow read returns the names of
every node tool and source, so editors can remove the owner's private
ones. An agent image is stored only once the save is known to go ahead.
arc53-machine
4d001f6a20