feat: support routes

[kkorus]

Hi, we could have an option to declare routes during plugin registration. That would help when using Fastify with NestJS where there is no option to set config on route like:

fastify.get('/en', { config: { rawBody: true } }, handler)

example usage:

  app.register(rawBody2, {
    field: 'rawBody',
    global: false,
    encoding: false,
    runFirst: true,
    routes: ['/api/user/v1', 'api/contact/v1'],
  });

[phmz]

Hello, I'm also interested in this feature, is there anything I can do to help? It would solve some of the issues we have with uploading files (fastify-multipart).

[Eomm]

I'm also interested in this feature, is there anything I can do to help?

Would you like to push some tests to complete this PR?

[kkorus]

Hi @Eomm, Yes, I will do this over the weekend.

[Tam2]

I'm interested in this change too, currently using global: true to work around this issue with nestjs

[Eomm]

Would you like to push this feature over the line?

I'm more than happy to land it 👍🏼

[Tam2]

Raised #14 which includes test cases