feat: add Procedure Duration/Time Slot settings and custom appointment type

- Add Settings > Advanced > Procedure Duration/Time Slot page with three sections:
  1. Procedure Duration: CDT codes with durations (editable table, save per section)
  2. Doctor Time Slot: drag-to-block visual grid (A/B/C columns, 8 AM–9 PM, edit/delete slots)
  3. Hygienist Time Slot: procedure descriptions with durations
- Backend: ProcedureTimeslot Prisma model, storage, and GET/PUT /api/procedure-timeslot route
- DB migration: procedure_timeslot table
- Appointment form: when type is "Other", show a free-text input for custom description; saved as other:<description> and decoded for display on the schedule card

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/Frontend/src/pages/appointments-page.tsx

@@ -817,7 +817,11 @@ export default function AppointmentsPage() {
           <Move className="h-3 w-3" />
           {appointment.patientName}
         </div>
-        <div className="truncate">{appointment.type}</div>
+        <div className="truncate">
+          {appointment.type?.startsWith("other:")
+            ? appointment.type.slice(6)
+            : appointment.type}
+        </div>
       </div>
     );
   }