As design explorations start taking shape (see T342542), we want to start thinking what's the best way to set up the microsite for the Wiki-Highlights experiment. As regular A/B tests go, the microsite set up will need to accommodate a random set of users for the highlight experience and another set of users for the long article experience ( see T343990)

Outcomes:

• Repo link: https://github.com/wikimedia/wiki-highlights
• 2 sub-tasks for the control & treatment groups: T345013 & T345014