Feature: Anvil Plugin Module for supporting custom RPC methods

[sambacha]

Component

Anvil

Describe the feature you would like

anvil plugin system

TLDR: Enable a plugin system to support creating new RPC methods without having to overly burden the maintenance of anvil

This is pretty broad, however, it may be worthwhile instead of endless feature requests

Additional context

cc @mat

[onbjerg]

Closing this as out of scope