Analyse missing features to implement the end to end user flow

### What should be done?

We need a comprehensive list of features that are currently missing to be able to use the MultiSig as described in #1

### How should it be done?

Analyse the current state of

- [ ] Miden wallet (https://miden.fi)
- [ ] Miden wallet adapter (https://github.com/demox-labs/miden-wallet-adapter and https://demo.miden.fi/send)
- [ ] Miden WebClient (https://github.com/0xMiden/miden-client/tree/next/crates/web-client)

with respect to the proposed user flow. Then, create one meta issue that describes the necessary changes and features to be able to implement the flow.

As an example:

- https://github.com/0xMiden/miden-client/issues/908 is missing to be able to sign the `hash( TransactionEffect || AUX )` in the WebClient and Wallet
- The Wallet cannot show the `TransactionEffect` yet
- ...

### When is this task done?

When we have that list and the Miden team considers it as complete.

### Additional context

_No response_