Add Missed status

backend/src/main/resources/db/migration/V18__past_appointments_missed.sql

@@ -0,0 +1,10 @@
+-- V18: Normalize past appointments.
+-- Any appointment that is still 'Booked' but the date/time has passed should be marked as 'Missed'.
+
+UPDATE appointment
+SET appointmentStatus = 'Missed'
+WHERE LOWER(appointmentStatus) = 'booked'
+  AND (
+    appointmentDate < CURRENT_DATE
+    OR (appointmentDate = CURRENT_DATE AND appointmentTime < CURRENT_TIME)
+  );