Add Comprehensive RPC and WebSocket Coverage for APIs

[aaronbuchwald]

This ticket is to add comprehensive RPC and WebSocket API coverage via e2e testing.

We should add unit testing where possible, but expect that setting up a simple e2e test that we can use to test API calls work correctly will significantly improve our test coverage.

Flood may be a good tool to add comprehensive coverage and benchmark performance: https://github.com/paradigmxyz/flood/