chore: use alloy zksync

[nbaztec]

Motivation

Migrate away from the unmaintained zksync-web3-rs.

Solution

Use alloy-zksync crate.

[Karrq]

Hmm I thought with alloy-zksync we could get rid of a lot of overrides, perhaps we are still lacking the necessary abstractions?
For example, we shouldn't need to have ZkCast, or so I thought - unless it's something that we can achieve, but in a separate PR

[nbaztec]

Cast uses Provider<AnyNetwork> whereas we need to use Provider<Zksync>, moreover the defined methods rely on concrete tx types defined on AnyNetwork::TransactionRequest an not on Zkysnc::TransactionRequest. So generalizing them doesn't give us much.

[Karrq]

Send it 🚀

[Jrigada]

LGTM