Artifact asset copy_from now supports cross-org destinations with a retry probe

The copy_from action, used to copy assets between artifacts, now supports copying across organizations in some cases. It checks organization membership and probe state to determine whether a cross-organization copy is allowed (crossOrgOk), and blocks the copy with a specific error if the destination artifact is outside the user's organization and not allowed. If the first copy attempt fails because the destination isn't found yet and hasn't been probed, Claude Code now automatically retries once with a fresh probe.