[Feature]: Mempool lanes

[tac0turtle]

Summary

Comet is working on mempool lanes as a major performance unlock for users. We had a call with the team to discuss the design and talk about implementation goals. The design is somewhat simple to use and would need a custom mempool implementation to take advantage of it. We could also adapt the existing mempool implementations to take advantage of it.

CometBFT tracking issue: cometbft/cometbft#2803
ADR: https://github.com/cometbft/cometbft/blob/main/docs/references/architecture/adr-118-mempool-lanes.md

Problem Definition

No response

Proposed Feature

1. look into modifying existing mempools to take advantage of this feature
2. if 1 is not possible implement a simple priority mempool that uses the lanes.