The public area pages describe the Magpie app only once it is released

The public pages about Magpie's areas described things done in the Magpie app, such as selling in person, before anyone can install it. Those parts are now hidden, and the page about selling in person (magpie.diy/point-of-sale) is not shown. They return, unchanged, the day the app is released, with one setting: MAGPIE_APP_RELEASED=1 in the site's .env.