eth/tracers/native: handle interrupt via proxy

[s1na]

This is mostly an experiment. The proxy is itself a pseudo-tracer that handles interrupts and only forwards events to the actual native tracer in case there's no interrupt. The goal is to make the actual tracing code cleaner.

[rjl493456442]

I think it's a nice idea :)

[holiman]

From https://github.com/ethereum/go-ethereum/pull/26086 :

Unrelated commit in the PR: I also moved EVM cancellation to be the API's responsibility instead of the tracer. I feel like it's more fitting.

IMO #26086 is cleaner, and makes this PR moot