create a new op-spammer component for deployment in devnets

[geoknee]

For v0, this would be a simple service which can be configured with a private key and ethereum RPC endpoint, and periodically sends any kind of user transaction to that endpoint.

This would help catch bugs on devnets which are all-too-often completely devoid of any kind of user traffic. This obscures problems and delays the discovery of bugs until we hit production networks.

This would be a good candidate to be written in Rust for any beginner Rustacean looking for a small task to onboard with.

Extensions for a v1:

• cycles through all transaction types (setCode, legacy, ...)
• fuzzes the calldata, to, amount fields
• maintains a high load of transactions, enough to fill blocks to 50%, 100%
• optimizes for recovering funds / not needing constant topups
• can be controlled over an RPC
• can be configured to send "spam" (calldata heavy transactions) or compute-heavy transactions (it could CREATE2 deploy a contract which allows for heavy compute and send transactions there).

[geoknee]

Prior art here may be all we need https://github.com/flashbots/contender

[scharissis]

Prior art here may be all we need https://github.com/flashbots/contender

Specifically https://github.com/flashbots/contender/issues/145