feat(readBody): validate requests with application/json content type

[tobiasdiez]

Follow-up from #201. Changes are:

• Throw error if content-type says the request body is json but the body is not valid json; uses the newly introduced strict mode from feat: add option strict that throws an error if the input is not valid JSON destr#11.
• Doesn't try to parse the body (as json) if content-type says its plain text
• Improve internal and external typing information. Fixes Wrong typing for readRawBody #223.
• Streamline codeflow in readBodyRaw

[tobiasdiez]

@pi0 this is now ready for review

[codecov]

Codecov Report

Merging #207 (4c36817) into main (a5c8c9f) will increase coverage by 0.38%.
The diff coverage is 98.48%.

@@            Coverage Diff             @@
##             main     #207      +/-   ##
==========================================
+ Coverage   77.36%   77.74%   +0.38%     
==========================================
  Files          26       26              
  Lines        2655     2692      +37     
  Branches      383      393      +10     
==========================================
+ Hits         2054     2093      +39     
+ Misses        601      599       -2     

Impacted Files	Coverage Δ
src/utils/body.ts	94.64% <98.48%> (+1.51%)	⬆️

... and 1 file with indirect coverage changes

[nopeless]

@tobiasdiez Nice pr; I ended up fixing the encoding signature too just to realize that you had a fix haha

[tobiasdiez]

@pi0 merged in the latest version from main, so this PR is ready for review again

[tobiasdiez]

@pi0 would appreciate if you could have a look at this PR. Thanks!

[T1B0]

@tobiasdiez good PR 👍
@pi0 i was considering doing a PR for adding size limit to parse body, should i start it from this branch or main ?

[Hebilicious]

@pi0 I think this is overall a good change, would like to know what you think before approving. We would need to keep the tests and refactor the logic, as there's a lot of conflicts now.

[pi0]

Hi, dear @tobiasdiez, and sorry for checking this late.

Before merging, I made a few changes to fix the behavior matching PR description (we strictly validate json body only when application/json is passing otherwise using default defu behavior with a try-parse strategy which also ensures this is a non-breaking change).

n the future please consider splitting fixes to allow iterating faster and having a clear changelog 🙏🏼

Cheers!