chore(api): Improve logging and error status code

[koistya]

If you're using import { log } from "./core" directly (as opposed ctx.log(...)), the res argument is now ommited:

import { log } from "../core";

// BEFORE
log(req, res, "WARNING", "Some text or object");

// AFTER
log(req, "WARNING", "Some text or object")

When used inside GraphQL type resolvers, nothing has changed:

async resolve(self, args, ctx) {
  ctx.log("ERROR", new Error(...));
}