feat: add request and response utils

[farnabaz]

This PR

• creates useQuery util to parse the query params of request.
• creates useBody util to parse raw and JSON payload of the request.
• Modify createError util to support runtime error to support runtime errors like validation errors.

[Atinux]

Would it be possible to open another PR for documenting them @farnabaz ?

[Atinux]

Also, shouldn't we rename them to getBody(req) that actually use destr by default and having getRawBody() instead?

[pi0]

Usage of body might be ambiguous for different responses but might rename useBodyJSON to useJSON for shorter name if it is better :)

Update: More thinking seems reasonable DX wise 😁

[farnabaz]

@Atinux I'll create PR for docs.
What about creating a docs project?

[Atinux]

I think README is enough for now, cc @pi0

[pi0]

Yeah. H2 is pretty much an experimental project now and i don't want to put energy on docs for in development utils. We may later on benefit jsdocs

[danielroe]

@pi0 It may be worth starting off with jsdoc comments as these can be more easily kept up-to-date with changes to API? I am happy to do that if you agree.

[pi0]

JSDocs seems better that would be nice if you are up to add them :)