feat: introduce eth_sendBundle

[wlawt]

Overview

This PR adds rpc support for send_bundle. The current validation logic is:

• A bundle cannot be more than 1 hour into the future
• A bundle cannot have 30M gas (totally changeable, just some placeholder)
• All transactions in a bundle must be valid

Other changes:

The Kafka topic key was changed from a sender address to the bundle hash. This aligns across the APIs since a bundle can have transactions from different senders. Alternatively, we could have the sender of the bundle, but this seemed like the simplest solution.

Tests

• CI
• Added unit tests
• Tested on devnet for behaviour changes on the refactor and everything is still the same

TODO

• Validate transactions in a bundle
• Implement: "If a bundle with the same bundle hash already exists the bundle will be combined with the existing one." of the API spec

Follow up PRs

• Expand on bundle validation criteria
• Enqueue BundleWithMetadata over EthSendBundle
• Implement replace bundle within send_bundle
• Implement e2e testing as such:
  • Update base/transaction-latency to do eth_sendBundle
  • Update base/infra-routing to support eth_sendBundle

[niran]

LGTM