From the app, when we can determine that the featured article data has changed since the last time we fetched it, clear out the widget cache and ensure featured article widget is reloaded. There are probably many places in the app that this could occur, but at the very least:

• When the Explore feed refreshes (either manually by user or automatically by the app), check the featured article. (This work is partially done in the featured-article-fix branch).
• When the featured article view controller is loaded.

Note: we'll want to do a similar thing for the other widget data (picture of the day, on this day, top read) when their Core Data dependency is removed.

Note for QA

Please regression test the Featured Article widget in TestFlight build 7.2.1 (2090)