feat: implement service bindings + local mode `dev`

Service bindings ([services]) works with remote mode in wrangler dev, we should figure out how to do the same for local mode. This is part of the broader picture for multi worker, but filing this as a followup for https://github.com/cloudflare/wrangler2/pull/906 anyway.

[threepointone]

Hey @chrstntdd, would you like to try the solution we just landed in wrangler@beta? You simply have to run wrangler dev --local on both workers in different terminal tabs, and they should automatically bind to each other.

[chrstntdd]

Ah yeah, apologies for leaving that bit out. It’s not too involved at the moment, but it goes like this:

// env.ts

// `ENV` is injected by the build scripts with process.env.NODE_ENV or equivalent.
export const API_ENDPOINT = ENV === "production" ? "https://api.<WORKER>.com" : "http://localhost:3001"

And the usage within the application like so:

import { createResource } from "solid-js"

import { API_ENDPOINT } from "./config/env"
import { useFetch } from "./global-ctx"

export function App() {
  let fetch = useFetch()
  let [x] = createResource(`${API_ENDPOINT}/get-some-data`, async (key) => {
    let content = await fetch(key)
    return content
  })

  return (
    <section>
      <div>SSR data from worker:</div>
      <pre>{JSON.stringify(x(), null, 2)}</pre>
    </section>
  )
}