implement same parsing logic on server and frontend

Server now downloads the HTML file via new endpoint but the parsing logic now happens in
the browser. The reason for this is to have a way same code for both
environments.

If the JavaScript is disabled, it's still possible to call the previous
endpoint and download the file from the server.

lib/static/app/crawler.js

@@ -0,0 +1,20 @@
+const crawl = async (url, { logger }) => {
+  if (logger) {
+    logger.log({
+      message: `Crawl started for url: ${url}`,
+      level: 'info',
+      service: 'parser',
+    })
+  }
+
+  return new Promise((resolve, reject) => {
+    fetch(url, {
+      method: 'GET',
+    }).then((response) => {
+      console.log(response)
+      resolve()
+    }).catch(reject)
+  })
+}
+
+export default crawl