Use webpack for bundling JS libs and move Golang code related to Iframe generation there

javascript/src/viamapi-iframe.js

@@ -2266,6 +2266,8 @@ const connection = Penpal.connectToParent({
 connection.promise.then(parent => {
   var identities = localStorage.getItem("identities")
 
+  window.API_HOST = `${window.location.protocol}//${window.location.host}/`;
+
   console.log("Library loaded at: " + new Date().toISOString())
 
   if (identities === "" || identities === null) {