How do you deploy Angular 2 apps once they reach the production phase?
All the guides I've seen so far (even on angular.io) are counting on a lite-server for serving and browserSync to reflect changes - but when you finish with development, how can you publish the app?
Do I import all the compiled
You are actually here touching two questions in one. First one is how to host your application. And as @toskv mentioned its really too broad question to be answered and depends on numerous different things. Second one is more specific - how do you prepare the deployment version of the application. You have several options here:
Yes you will most likely need to deploy systemjs and bunch of other external libraries as part of your package. And yes you will be able to bundle them into just couple of js files you reference from your html page. You do not have to reference all your compiled js files from the page though - systemjs as a module loader will take care of that.
I know it sounds muddy - to help get you started with the #2 here are two really good sample applications:
SystemJS builder: angular2 seed
WebPack: angular2 webpack starter
Look how they do it - and hopefully this will help you to find your way of bundling apps you make.