S16 postgresql opslag added

agiledancers-fe/src/app/shared/group-members.ts

@@ -57,6 +57,8 @@ import { DialogFrame } from './dialog-frame';
   `,
 })
 export class GroupMembers implements OnInit {
+  readonly revision = input<number>();
+  private originalRevision?: number;
   readonly schoolId = input.required<number>();
   readonly group = input.required<DanceGroup>();
   readonly dancers = input.required<Dancer[]>();
@@ -70,6 +72,7 @@ export class GroupMembers implements OnInit {
   );
   private readonly api = inject(SchoolApi);
   ngOnInit(): void {
+    this.originalRevision = this.revision();
     this.memberIds.set([...this.group().dancerIds]);
   }
   async toggle(dancerId: number, event: Event): Promise<void> {
@@ -82,7 +85,10 @@ export class GroupMembers implements OnInit {
     this.busy.set(true);
     this.error.set('');
     try {
-      await firstValueFrom(this.api.membership(this.schoolId(), this.group().id, dancerId, add));
+      await firstValueFrom(
+        this.api.membership(this.schoolId(), this.group().id, dancerId, add, this.originalRevision),
+      );
+      if (this.originalRevision !== undefined) this.originalRevision++;
       this.memberIds.update((ids) =>
         add ? [...ids, dancerId] : ids.filter((id) => id !== dancerId),
       );