Design restaurant shift scheduling

Design the backend for a restaurant workforce scheduling system. A company operates many restaurants. Each restaurant has employees and managers. Every week, a manager prepares the schedule for the following week and must publish the final version by Friday. Design a system that supports: - modeling companies, restaurants, employees, and managers - creating and editing a weekly schedule for a restaurant - assigning employees to shifts - publishing the schedule so employees can view the official version - handling many restaurants and growing traffic over time Focus especially on the data model, but also explain the high-level architecture, key APIs, scalability considerations, and how you would keep schedule data consistent.