feat(world-chain-builder): Enable PBH support for 4337 UserOps

[0xKitsune]

Currently, the World Chain Builder enables priority blockspace for humans via the PBH Tx envelope, allowing users to provide a World ID proof, setting the signal of the proof as the transaction hash.

While this mechanism enables any user with a valid World ID to create a priority transaction, this requires that a user has Eth in their account to pay for gas. PBH validation should also be extended to support 4337 UserOps, allowing a third party to submit a single UserOp with top of block priority on behalf of a World ID user.

4337 PBH Validation

A valid PBH UserOp needs to adhere to the following:

• The signal of the proof must be the hash of all 4337 UserOp fields concatenated together
• The to address of the transaction must be the Entrypoint contract
• The UserOp signature should be validated to ensure the proper sender and nonce is specified.
• The transaction calldata can only specify a single UserOp. Transactions that bundle multiple UserOps should not be provided priority blockspace

Tasks

• Extend RPC modules to implement eth_sendRawTransactionConditional #72