Function factory_proxy_init_code 

pub fn factory_proxy_init_code(artifacts: &Artifacts) -> Result<Bytes>

The frozen proxy init code: ERC1967Proxy creation code ++ abi.encode(implAddress, initialize(FACTORY_GENESIS_ADMIN)). Every byte is network-invariant; FactoryDeployer.proxyInitCode() produces the same bytes (asserted against the vendored artifacts by the Solidity tests).