Remove decorators and bundler workarounds

src/index.ts

@@ -1,18 +1,7 @@
 declare module '@webcomponents/custom-elements';
 
-// Patch Worker to ignore `importScripts("x.css")` generated by Parcel:
-const W = self.Worker;
-self.Worker = function (url: string | URL, options?: WorkerOptions) {
-  const code = `
-    importScripts=(function(){
-      return this.apply(self,[].slice.call(arguments).map(function(x){return !/\\.css$/i.test(x) && new URL(x,self.url).href}).filter(Boolean))
-    }).bind(importScripts);importScripts(self.url=${JSON.stringify(url)})
-  `.trim();
-  return new W(URL.createObjectURL(new Blob([code], { type: 'text/javascript' })), options);
-} as any as (typeof Worker);
-
 function init() {
-  require('./init-app.tsx');
+  import('./init-app.tsx');
 }
 
 if (!('customElements' in self)) {