This doesn't really have anything to do with Blockly per se, but I took a look at your web app and your code. The first thing I did was to look at your browser's console log. From there I saw some errors like:
Uncaught ReferenceError: URI_HARDWARE is not defined
at fetchJavaScriptForHardwareViaHttp (hardware_util.js:58:19)
...
and
Uncaught ReferenceError: PARAM_NAME is not defined
at newProjectViaHttp (project_util.js:239:16)
...
Then I took a look at the code in the files mentioned on those stack traces and saw:
// The following are generated dynamically in ProgrammingModeServer.fetchJavaScriptForServer():
So, it seemed relatively clear that those variables need to be defined by calling some function called fetchJavaScriptForServer, but you don't have any such function defined in your code. Doing some further software archeology, I believe that this comes from some code that you can see here (although I suspect the original genesis for this code was from our friend Liz Looney). The bottom line is that if you want to run this code unchanged you'll probably also need to run a Java server like the one in the OpenFTC/OpenRC-Turbo repo.
Hope this helps.
-Mark