Should we retrieve the samples from dart_services?

[parlough]

Right now if we want to update the samples, users will have to redownload the entire JS bundle. Plus the JS bundle includes the samples whether they will use them or not.

If we instead exposed them through a dart_services API, users would be able to use the cached JS bundle longer, the initial bundle would be smaller, and theoretically different channels could support different samples. This could be helpful for handling breaking changes, showcasing an experimental feature (extension types, macros, etc).

The one downside is extra implementation complexity that comes with this, but I thought I'd open the discussion for thoughts :)