Adding a `create` or `init` account procedure

For the multisig wallet, it would be useful for the approvers to see that the multisig account is already onchain before signing the first `TransactionSummary`.

While this is not **necessary** to sign the right `TransactionSummary` (and we get all the required info from it), it might feel off to sign updates for a "non-existing" account.

What do you guys think?

(separately, this could be useful for `BasicWallet` too - it would provide an explicit way of creating a tx, which might be good for the UX).

Inspired by a [Slack discussion](https://midengroup.slack.com/archives/C09308USC5U/p1753944579626299) with @VAIBHAVJINDAL3012