sachingithu/appointment ? reverse-engineered prompt

Build me a simple appointment booking system with separate services for doctors, patients, appointments, an API gateway, a service registry, and an admin server.

I want the app to let patients be added and viewed, doctors be added and viewed, and appointments be created between them. The gateway should be the single entry point for the app, and the services should talk to each other cleanly. Make it feel like a real microservices project, with each part running on its own and connecting through service discovery.

Please set it up so I can start the services locally and test the basic flow end to end. Keep the code clean and easy to understand, with a simple structure that would make sense for a small healthcare scheduling app. If you need to look up current Spring docs online, go ahead.