feat: move to `compress` and `decompress` route specific options, improved typescript types and tests, reorganize tests

[darkgl0w]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the feature has not already been requested

🚀 Feature Proposal

Hello,

following the PR #196, I would like to work on a few things for this package that will help improve development experience:

• Add compress and decompress route shorthand configuration properties
• Improve typescript types and actually test those types
• Update the documentation
• Reorganize and/or rewrite tests (renaming files following xxx.test.js convention, making groups with sub-tests, ...)

Note: some of those changes are breaking changes and will require a major bump.

If you think my proposal is acceptable the first 3 points are covered by this PR #199.

Regards.

Motivation

• It will follow the way over official packages define specific route options, it will be shorter ( 🤣 ) and more intuitive.
• It will have complete typings and those types will actually be tested.

Example

Current way to configure specific route options:

'use strict'

const zlib = require('zlib')
const fastify = require('fastify')()

fastify.register(require('fastify-compress', { global: false })

fastify.get('/one', {
  config: {
    compress: { createGzip: () => zlib.createGzip() },
    decompress: { createGunzip: () => zlib.createGunzip() }
  }
}, (request, reply) => {
 // ...
})

fastify.route({
  method: 'GET',
  path: '/two',
  config: {
    compress: { createGzip: () => zlib.createGzip() },
    decompress: { createGunzip: () => zlib.createGunzip() }
  },
  handler: (request, reply) => {
   // ...
  }
})

New way to configure specific route options:

'use strict'

const zlib = require('zlib')
const fastify = require('fastify')()

fastify.register(require('fastify-compress', { global: false })

fastify.get('/one', {
  compress: { createGzip: () => zlib.createGzip() },
  decompress: { createGunzip: () => zlib.createGunzip() }
}, (request, reply) => {
 // ...
})

fastify.route({
  method: 'GET',
  path: '/two',
  compress: { createGzip: () => zlib.createGzip() },
  decompress: { createGunzip: () => zlib.createGunzip() },
  handler: (request, reply) => {
   // ...
  }
})

[darkgl0w]

I have started to work on the last part of the proposal with a big overhaul on tests :
reorganize and/or rewrite tests (renaming files following xxx.test.js convention, making groups with sub-tests, ...).

I will submit a PR after the landing of #199