Master access state for a business's public page. public is the normal state. private gates the page itself: non-staff visitors get a 404 as if the business didn't exist, while staff with access still see the full public experience (with a "Private" indicator), and the business is excluded from every discovery and search surface regardless of the finer-grained BusinessVisibility flags. Lets an operator stand up and rehearse a store end-to-end before going live.