Add link to demo deck on homepage

[ejm714]

Adds a sentence with a link to the demo deck to the top section of the home page. Alternatively, we could make this its own tab to feature it more prominently. Not strongly opinionated on where it goes, just wanted to make the demo deck publicly available.

[render]

Your Render PR Server URL is https://cyfi-pr-140.onrender.com.

Follow its progress at https://dashboard.render.com/static/srv-cmngoknqd2ns73clse20.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (140686c) 75.0% compared to head (245d121) 75.0%.

Additional details and impacted files

@@          Coverage Diff          @@
##            main    #140   +/-   ##
=====================================
  Coverage   75.0%   75.0%           
=====================================
  Files         12      12           
  Lines        863     863           
=====================================
  Hits         648     648           
  Misses       215     215           

[klwetstone]

@ejm714 Good idea! LGTM. I like how you included it as a link rather than directly featured on a page. To me, it makes it clearer that the first-stop "entry point" for using the package is the homepage of the docs, and the deck is useful supplementary material.

Also the deck is just ✨ ✨ -- there are some new slides I hadn't seen!