- Declare 'localhost' network in hardhat.config.ts pointing to
http://127.0.0.1:8545 (chainId 31337) so deploy scripts work
against an external Anvil/Hardhat node.
- Make MNEMONIC and ALCHEMY_API_KEY optional: fall back to the
Hardhat/Anvil deterministic mnemonic when MNEMONIC is missing,
and only require ALCHEMY_API_KEY when targeting public networks.
- Reset deploys/localhost.json to a starter state (signers populated,
contract addresses empty) so the frontend e2e setup writes fresh
addresses on every run.
