docs: add documentation for cloudfront

[CaptainCarpensir]

Adds a developing page, and adds the corresponding fields which have been added to the environment manifest

Documents features built for #3701 milestone 1

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the Apache 2.0 License.

[huanjani]

This looks great! You managed to make a potentially confusing feature very clear. Just a few nits.