Do not deploy.

Workspace: the job starts from an empty tree (no foundry.toml, forge-std or OpenZeppelin) and each worker may write only the listed src files and their test/.t.sol files, so no dependency can be added. Write everything inline (pragma ^0.8.24, default forge layout, no imports beyond these files); mocks and helper contracts live inside the test files, which declare the cheatcodes they use in an inline Vm interface at the HEVM address and assert with require.

So EIP-712 hashing and signature recovery are inline too, not OpenZeppelin's ERC2771Forwarder, ERC2771Context, EIP712 or ECDSA.

Forwarder: EIP-712 domain {name "Forwarder", version "1", chainId, verifyingContract}; ForwardRequest(address from, address to, uint256 value, uint256 gas, uint256 nonce, uint48 deadline, bytes data). nonces(from) is one sequential nonce per signer. verify(request, signature) view is true only for a signature by from (low s), the current nonce, deadline >= block.timestamp, and a to whose isTrustedForwarder(address(this)) returns true. execute(request, signature) payable requires verify and msg.value == value, consumes the nonce before the call, calls to with exactly gas gas and abi.encodePacked(data, from), then checks gasleft() > gas / 63 and reverts otherwise (the EIP-150 guard against a relayer starving the inner call).

If the inner call reverts, execute reverts with its revert data, so the nonce is not spent. Emits ExecutedForwardRequest(from, nonce).

Recipient: constructor(address trustedForwarder) immutable; isTrustedForwarder(address); _msgSender() returns the last 20 bytes of calldata only when msg.sender is the trusted forwarder and calldata is at least 20 bytes, else msg.sender; _msgData() strips them. increment() adds 1 to counts[_msgSender()] and payable deposit() credits balances[_msgSender()].

No multicall: document in NatSpec why a self-delegatecall multicall would let a forwarded caller spoof any address (the 2023 ERC-2771 + Multicall issue).

Tests: a relayed increment and deposit credit the signer, not the relayer; a replayed request, an expired deadline, a wrong signer, a signature for another chainId or forwarder, a to that does not trust the forwarder and a msg.value mismatch all revert; a relayer that supplies too little gas makes execute revert; a direct call from a non-forwarder with 20 appended bytes cannot spoof the sender; an inner revert bubbles up and leaves the nonce unused.