bloXroute MEV Validator

[Uri-Margalit-bloXroute]

Description

This PR allows a validator node to utilize bloXroute MEV services. The validator node

registers itself to MEV relay upon restart or an epoch change
processes eth_proposedBlock from MEV relays

Rationale

The introduction of mev-boost in Ethereum enabled a win-win situation for Searchers, Block builders and Proposers which allows all three to profit off of potential arbitrage opportunities, and do so not at the expense of other traders and dApps executing transactions on chain.

This PR implements the validator to MEV relay integration

Example

eth_proposedBlock endpoint receives

{
   "id": "1",
   "method": "eth_proposedBlock",
   "params": [{
      "mevRelay": "bloXroute",
      "blockNumber": "0xba10d0",
      "prevBlockHash": "0xabc123...555",
      "blockReward": 1230000000000000,
      "gasLimit": 140000000,
      "gasUsed": 70000000,
      "payload": ["ab..ab", "cd..cd"],
   }]
}

Changes

Notable changes:

• Added couple of startup argument
  • miner.mevrelays - list of uris of MEV relays the validator works with
  • miner.mevproposedblockuri - the callback uri which the MEV relay should send the proposed blocks
• Added web3 endpoint eth_proposedBlock - the MEV relays use this endpoint to send their proposed blocks
• Added a logic in the miner to validate the proposed blocks from the MEV relays and consider them when the validator choose which block it should propose