Support account's execute

This is different from #6. The account interface exposes an execute method to invoke multiple external functions in one transaction.

The proposed interface is:

const { execute, loading, error } = useStarknetExecute()

Where execute is:

execute: ({ calls: CallArgs, metadata?: any }) => Promise<AddTransactionResponse | undefined>
type CallArgs = { args?: T, contract?: Contract, method?: string }

Example

const { token } = useTokenContract()
const { other } = useOtherContract()

const { account } = useStarknet()
const { execute } = useStarknetExecute()

const [amount, setAmount] = useState(0)

// ...

execute({
  metadata: { message: 'Approve token and swap' },
  calls: [
    { contract: token, method: 'approve', args: amount && account ? [amount, account] : undefined },
    { contract: other, method: 'swap', args: amount && account ? [amount, account /*, more data here */] : undefined },
  ]
})

Like invoke, execute checks that all calls arguments are defined before making the call.

[ponderingdemocritus]

Pulled from StarkNet fees - This is a huge potential saving if we batch transactions.

[tarrencev]

I like the proposed interface for execute. I’m wondering if we should deprecate invoke api in favor of a single execute api. It seems that is the direction the AccountInterface has taken:

public abstract execute(
    transactions: Call | Call[],
    abis?: Abi[],
    transactionsDetail?: InvocationsDetails
  ): Promise<AddTransactionResponse>;