feat(#172): API absences-garde (liste, CRUD, droits parent/AM).

GET placement|all, POST/PATCH/DELETE, expire_at, tests unitaires.

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

backend/src/app.module.ts

@@ -16,6 +16,7 @@ import { AllExceptionsFilter } from './common/filters/all_exceptions.filters';
 import { EnfantsModule } from './routes/enfants/enfants.module';
 import { AppConfigModule } from './modules/config/config.module';
 import { DocumentsLegauxModule } from './modules/documents-legaux';
+import { AbsencesGardeModule } from './modules/absences-garde';
 import { RelaisModule } from './routes/relais/relais.module';
 import { DossiersModule } from './routes/dossiers/dossiers.module';
 import { SuppressionsModule } from './routes/suppressions/suppressions.module';
@@ -56,6 +57,7 @@ import { SuppressionsModule } from './routes/suppressions/suppressions.module';
     AuthModule,
     AppConfigModule,
     DocumentsLegauxModule,
+    AbsencesGardeModule,
     RelaisModule,
     DossiersModule,
     SuppressionsModule,