Add fetchWorker for fetching off the main thread

src/workers/fetch.worker.ts

@@ -0,0 +1,17 @@
+import { Comlink } from '@/deps.ts';
+
+export const FetchWorker = {
+  async fetch(url: string): Promise<[BodyInit, ResponseInit]> {
+    const response = await fetch(url);
+    return [
+      await response.text(),
+      {
+        status: response.status,
+        statusText: response.statusText,
+        headers: Array.from(response.headers.entries()),
+      },
+    ];
+  },
+};
+
+Comlink.expose(FetchWorker);