Added Vite bundler support, Channels & Async functions

[Roba1993]

To support the Vite bundler (and possible others), I figured out, that providing the wasm.js file as a path is not enough. Additionally also the direct path to the was.wasm file need to be provided. If both are delivered correctly it's working. This solves my issue #4.

The implementation simply adds a new path for the actual wasm file. Please let me know, when the naming is still a bit off.

Following my example code from my index.js file loaded with Vite:

import wasmUrl from "../pkg/webapp.js?url";
import wasmBgUrl from "../pkg/webapp_bg.wasm?url";
import init, {
  main,
  initWorkerPool,
  WorkerPoolOptions,
} from "../pkg/webapp.js";
async function run() {
  // main app init and run
  await init();
  main();

  // web worker setup
  let options = new WorkerPoolOptions();
  options.path = window.location.origin + wasmUrl;
  options.path_bg = window.location.origin + wasmBgUrl;
  options.num_workers = 4;
  initWorkerPool(options);
}
run();

This leaves one problem for now. Using the worker pool is only possible after it has been fully loaded. With this configuration the main rust code is running before the WebWorkerPool is fully initialized. Using it inside rust before will create a new default one which will fail. This is due to the actual implementation here.

wasmworker/src/global.rs

Line 50 in 9251271

.get_or_init(|| async {

Could this be changed to something which is waiting until the pool is ready?

My local workaround for this is the following ugly code:

pub async fn ww_pool() -> &'static wasmworker::pool::WebWorkerPool {
    while !wasmworker::has_worker_pool() {
        sleep(Duration::from_millis(100)).await;
    }
    wasmworker::worker_pool().await
}