feat(#159): suppressions métier dossiers/parents/enfants/AM/staff.

SuppressionService + DELETE /dossiers/:numero, cascades DELETE /users et
DELETE /enfants?deleteDossier, flag sans_enfant, specs front #160.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/src/routes/dossiers/dossiers.module.ts

@@ -5,6 +5,7 @@ import { JwtModule } from '@nestjs/jwt';
 import { Parents } from 'src/entities/parents.entity';
 import { AssistanteMaternelle } from 'src/entities/assistantes_maternelles.entity';
 import { ParentsModule } from '../parents/parents.module';
+import { SuppressionsModule } from '../suppressions/suppressions.module';
 import { DossiersController } from './dossiers.controller';
 import { DossiersService } from './dossiers.service';
 
@@ -12,6 +13,7 @@ import { DossiersService } from './dossiers.service';
   imports: [
     TypeOrmModule.forFeature([Parents, AssistanteMaternelle]),
     ParentsModule,
+    SuppressionsModule,
     JwtModule.registerAsync({
       imports: [ConfigModule],
       useFactory: (config: ConfigService) => ({