The standard for web is basically the same since the beginning. A folder with a index.html and all other needed files.
All I'm saying if you zip a folder that contains a web app, it will work in any device without much effort.
A web bundle may never exist and you need to wait for the browsers to start supporting it in maybe if we are luck a few years.
If there's a tool to just zip the web app folder, hash it and upload it to some blossom servers them you can build a web app directory that anyone can use, verify etc