feat: implement Block-STM execution

[meyer9]

📝 Summary

Implements the Block-STM paper with some slight changes:

• Cancellation: execution can be cancelled midway through if the block deadline is reached. In this case, execution tasks will stop, but validation tasks will continue until validation_idx is reached so we know which transactions can be safely committed.
• Balance increments: For the fee beneficiary, balance increments are recorded separately instead of reading/writing the balance. Balance increments are still added to the write set, but not the read set. If a tx needs to read the balance of the fee beneficiary address, a read dependency is created and won't be resolved until all txs that previously wrote to the balance are resolved. At the end of the block, all fee increments are applied to the state at once. This prevents every tx from conflicting with the next one due to the read/write conflict on the fee beneficiary balance.

💡 Motivation and Context

Make op-rbuilder faster.

Open questions

• Limit checking: I think we can implement this with a two-phase resumable execution.
  • All txs will conflict on a GasUsed state key, but if they only conflict on that key, we can just recheck limits without rerunning the EVM.
• GAS opcode: This currently returns an incorrect value. We should mark this as a separate read from limit checking since it can affect EVM execution. All previous txs will need to be executed before this one can be re-executed. Nvm, this only applies to the tx gas left not the block.

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✅ I have completed the following steps:

• Run make lint
• Run make test
• Added tests (if applicable)