feat(types): serialize id in Response before result/error fields

[ArtificialPB]

Motivation

This change makes it possible to avoid buffering the result before being able to know how to decode it when using streaming response decoders.

For example, when using a WS connection, the client must track request ID's to know how to decode a response returned by the server. When using streaming-based JSON deserializers, you must buffer the result until you deserialize the ID of the response. This is wasteful for large / frequent messages.

Buffering example from a library we're developing: https://github.com/Kr1ptal/ethers-kt/blob/master/ethers-providers/src/main/kotlin/io/ethers/providers/WsClient.kt#L385-L394

Solution

Buffering can be avoided if the response serializes the ID before the result. The serialize function of Request type was updated to include the id field before result/error, see types/src/response.rs file changes. All other changes were made to update hardcoded test responses.

[niklasad1]

Do you have any hunch of much of perf benefit this is or data (benchmarks)? The fix is trivial so looks good to me

[lexnv]

LGTM!

[ArtificialPB]

@niklasad1 based on a quick profiling run, buffering in ethers-kt takes about 50% of the decoding time, and increases the amount of generated garbage by around the same ratio.

Decoding is still fast with buffering, but it's much better without :)