cloud: Add Goals section

[tsenart]

As per discussion on https://threads.com/34382402992 and a live meeting
to come up with the longer term goals for the team.

[keegancsmith]

I like this goal. 1 line that is easy to remember. Also clear way to guide any work you do. 👍

[nicksnyder]

This goal is missing two things according to the documentation in #1177:

1. A named owner
2. A clear definition of success (i.e., it should be defined in a way that there should be no ambiguity about whether it is "done" or not).

If you don't think these are helpful things to define for a goal, then please comment on that PR.

[tsenart]

This goal is missing two things according to the documentation in #1177:

Since that PR has since been merged, I'd like to discuss those two points in the product eng sync meeting tomorrow. Merging for now.