Get access to the engine functions in reth-sdk

[ferranbt]

Describe the feature

Similar to this example. I want to create an overlay implementation for some of the engine API methods, my implementation would add some custom logic (i.e. logging) and then call the inner engine logic.

However, unlike the EthAPI, there is no available access to call the Engine API methods.

Additional context

My ideal solution would be to have a function engine_api() in the registry like this that I can use to call the engine api methods.

[mattsse]

ref #16176

[nadtech-hub]

I'd like to work on this