consistent function naming
Function names should use mixedCase according to the Solidity style guide: https://docs.soliditylang.org/en/v0.8.16/style-guide.html#function-names

Currently, we have new_swap, set_ready, claim, refund, and verifySecret. So I propose new_swap => `newSwap` (or maybe make it an actionable verb phrase like `createSwap` or `initSwap`), set_ready => `setReady`.

The same goes for local state variables. So perhaps `timeout_0` => `timeout0` and `timeout_1` => `timeout1`. But these are less important.