ENS L2 Support (zkSync demo)

This project implements the first L2 support showcase for ENS with zkSync. While users can enjoy the benefits of their ENS names as usual on L1, they are now blessed with ~130x fewer gas fees and faster transaction speed. This project is also an example that can be replicated on other L2 chains to unlock further diversified scenarios.

This project follows https://eips.ethereum.org/EIPS/eip-3668 and implements (1) a L1 offchian resolver, (2) a public gateway, and (2) a L2 public resolver and registry. The contracts are written in Solidity, and deployed on Ethereum and zkSync with Hardhat. The gateway is written in node.js and deployed on GCP, it's using zksync-web3 for communication with zkSync contracts.