The iOS app currently fetches a config file located at https://meta.wikimedia.org/w/extensions/MobileApp/config/ios.json whenever the app becomes active. This task is to:

• Check for a flag in that config file, if flag is there, clear cache and reload the widgets.
• Consider that the app may be foregrounded several times that day while a flag exists. We should only need to clear once, so this flag may need to be a unique identifier that then gets persisted to device and checked against so that we aren't clearing the cache all day.
• Config file flags can then be removed server-side the next day so that app stops clearing the cache.