GitLab

This MR adds

1. the getAppointments method to the AppointmentService class in the appointment-services.ts file. The method allows fetching appointments with query parameters such as patient name, patient ID, appointment date, hospital, and appointment status.
2. the association between the Appointment model and the Patient model in the Appointment.ts file. The Appointment model now belongs to the Patient model using the foreign key patient_id.