Return shape of useExecute. execute resolves once the ledger has executed rather than
at submission, and throws when nothing is connected or no party is reported; lastTx follows
the wallet's own txChanged pushes, so it moves even while execute is still pending.
Return shape of useExecute.
executeresolves once the ledger has executed rather than at submission, and throws when nothing is connected or no party is reported;lastTxfollows the wallet's owntxChangedpushes, so it moves even whileexecuteis still pending.