improvement: appointment dialog UX improved.

backend/src/modules/appointments/appointments.service.ts

@@ -104,11 +104,18 @@ export class AppointmentsService {
         patient: {
           select: { id: true, firstName: true, lastName: true, mobile: true },
         },
+        treatment: { select: { id: true } },
       },
       orderBy: [{ startAt: 'asc' }],
     });
 
-    return { success: true, data: items };
+    return {
+      success: true,
+      data: items.map(({ treatment, ...appointment }) => ({
+        ...appointment,
+        hasTreatment: Boolean(treatment),
+      })),
+    };
   }
 
   async create(
@@ -202,6 +209,18 @@ export class AppointmentsService {
     const providerUserId = dto.providerUserId ?? existing.providerUserId;
     const purpose = dto.purpose ?? existing.purpose;
 
+    if (dto.patientId && dto.patientId !== existing.patientId) {
+      const linkedTreatment = await this.prisma.treatment.findUnique({
+        where: { appointmentId: id },
+        select: { id: true },
+      });
+      if (linkedTreatment) {
+        throw new BadRequestException(
+          'Cannot change the patient while a treatment is linked to this appointment',
+        );
+      }
+    }
+
     this.treatmentCatalog.assertKnownTreatmentType(purpose);
 
     await this.ensurePatientInOrg(patientId, organizationId);