chore: remove direct tracing calls from proc-macros

[DaniPopes]

This significantly reduces the amount of code generated by the rpc macro.
I've also taken the liberty to refactor some of the proc macro code to make it more maintainable.

For example, on the reth-rpc-api crate (just #[rpc(server)]):

• before:
  • cargo expand: 156,020 LoC
  • cargo check -p after cargo clean -p: 3.1s
• after:
  • cargo expand: 73,276 LoC
  • cargo check -p after cargo clean -p: 1.7s

[niklasad1]

LGTM, thank you

[lexnv]

Nice!

[DaniPopes]

Hey @niklasad1 anything left to do here?

[jsdw]

LGTM!

One thing I wonder is; how do we avoid regressing again in this area? Maybe worth adding a CI check which expands some macros and logs the lines or something, so we get a feeling for changes over time and can note any large differences.