EIP-7791: GAS2ETH opcode: direct conversion of gas into ether

EIP-7791 proposes a new EVM opcode, GAS2ETH, that lets smart contracts convert gas directly into ETH so that contract authors and public goods projects can be compensated in proportion to their contracts' usage. Authors Charles Cooper and pcaversaccio created the draft, dated 2024-08-13, which requires EIP-2929. Under the specification, each transaction has a global GAS2ETH budget equal to its gas limit, and each call frame receives a local allowance derived from the gas forwarded to it. The proposed opcode cost matches the recently proposed PAY opcode, and the draft's test cases and reference implementation are still marked TBD.