Your account survives a dead zone

Fixed

• Signed in without signal: Opening the app where the phone could not reach the server used to run that whole session as signed out. Your account is now read from the phone first, and the server is asked again as soon as there is signal.
• Photo on the summary: The Add photo tile at the top of the finished-workout page was missing after such a launch. It shows again.
• Challenge check-in: A workout finished during one of those sessions was never counted in your challenge. It counts now, and the ones already on your phone are sent the next time the app opens signed in.
• Feature introduction: The introduction to a new feature no longer comes up right after a workout, where the routine changes and badge sheets belong. It waits for the next time you open the app.