Finish bundling JS/CSS #106
Description
@pascallaliberte The highest importance is how to bundle, distribute, and import everything.
- Review build scripts and bundling in this PR Use the dummy app as a built-in web app to test the gem #99 and make sure everything looks correct
- Test and confirm this new bundling works with client applications using esbuild, webpacker, and/or import maps
- Add documentation for adding the gem with esbuild, webpacker, and/or import maps
- Import the CSS from bullet train and CF and bundle with the gem so that in a "blank" rails application the styling works. (this is testable inside the gem I believe)
- Add instructions for teams on how to (specifically) override CSS classes for custom behavior.