Snapped menus stay on your phone, and error states are safer

A snapped menu is saved on your device once it's ready, so it opens instantly next time and works without a connection.

A few safety fixes came with it. If a shared profile can't be loaded, you now see a clear error with a retry, not an empty profile that could read as "no allergies". Profile names can't be left blank or duplicated. And deleting a profile also removes its key from your device.