feat: Initial support for custom paymaster

[Jrigada]

Motivation

We're enhancing our ZKSync specific capabilities by implementing paymaster functionality. This allows for sponsored transactions, improving user experience by enabling third parties to cover gas fees on behalf of users. More info about paymaster here as well as some examples.

Solution

1. Added new cheatcode zkUsePaymaster
2. Extended Cheatcodes inspector struct with paymaster_params
3. Updated CheatcodeTracerContext to include paymaster data
4. Added new test

Testing Approach

1. New tests in Paymaster.t.sol:
   • testCallWithPaymaster: Verifies paymaster usage in function calls
   • testCreateWithPaymaster: Tests paymaster usage in contract creation
   • testFailPaymasterBalanceDoesNotUpdate: Highlights an issue with observing paymaster balance changes

Note

• Balance changes of the paymaster contract are not observable from within the test environment. It seems the VM does not report back the modified L2BASETOKEN slot of the paymaster contract. As far as I observed the intended way of testing the paymaster usage is checking the user balance and that is what we are doing now in the test cases. Also to be sure while writing the tests we made sure the paymaster balance is decreasing inside its own contract, this is just not updated from the outer test contract.

Extra: We are depending on a third party dependency until this issue is resolved.