Annotate logs with load balancer traces

[gnarea]

For example, in Fastify, we'd have to do something like this on GCP per fastify/help#360:

  await server.addHook('onRequest', (request, reply, done) => {
    if (typeof request.id === 'string') {
      const [trace, spanId] = request.id.split(';')[0].split('/');
      const bindings = {
        'logging.googleapis.com/spanId': spanId,
        'logging.googleapis.com/trace': `projects/<GCP_PROJECT_ID>/traces/${trace}`,
      };
      request.log = request.log.child(bindings);
      reply.log = reply.log.child(bindings);
    }
    done();
  });

I've just tested it in relaycorp/cloud-gateway@ad8c8a5:

TODO

• Implement @relaycorp/pino-cloud-tracing library to generate child logger from a trace id like X-Amzn-Trace-Id or X-Cloud-Trace-Context (GCP).
• Implement @relaycorp/fastify-lb-tracing Fastify plugin using the library above.
• Integrate @relaycorp/fastify-lb-tracing in PoWeb service.
• Integrate @relaycorp/fastify-lb-tracing in PoHTTP service.
• Integrate @relaycorp/pino-cloud-tracing in PoWeb's WebSocket endpoint.
• Integrate @relaycorp/pino-cloud-tracing in CogRPC service.