feat(#195): SSE realtime Cartes (stream + emit audience)

GET /api/v1/cards/stream (Bearer ou ?access_token=).
Events card.created|updated|deleted, response.added + heartbeat.

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

backend/src/modules/cards/cards.service.ts

@@ -32,6 +32,7 @@ import {
   MajCarteDto,
   RepondreCarteDto,
 } from './dto/cards.dto';
+import { CardsRealtimeService } from './cards-realtime.service';
 
 @Injectable()
 export class CardsService {
@@ -49,6 +50,7 @@ export class CardsService {
     @InjectRepository(ParentsChildren)
     private readonly parentsChildrenRepo: Repository<ParentsChildren>,
     private readonly absencesService: AbsencesGardeService,
+    private readonly realtime: CardsRealtimeService,
   ) {}
 
   async listerTypes(role: RoleType): Promise<CardType[]> {
@@ -164,7 +166,9 @@ export class CardsService {
     await this.buildAudience(saved, type, placement, userId, role);
 
     const full = await this.loadCard(saved.id);
-    return this.toDto(full, userId);
+    const dtoOut = this.toDto(full, userId);
+    this.emitAudience(full, 'card.created', dtoOut);
+    return dtoOut;
   }
 
   async repondre(
@@ -228,7 +232,14 @@ export class CardsService {
 
     card.purge_at = this.purgeAt(card.type.retention_days, card.statut);
     await this.cardsRepo.save(card);
-    return this.toDto(await this.loadCard(cardId), userId);
+    const full = await this.loadCard(cardId);
+    const dtoOut = this.toDto(full, userId);
+    this.emitAudience(full, 'response.added', {
+      action: dto.action,
+      card: dtoOut,
+    });
+    this.emitAudience(full, 'card.updated', dtoOut);
+    return dtoOut;
   }
 
   async majEnAttente(
@@ -273,7 +284,10 @@ export class CardsService {
     card.statut = CardInstanceStatutType.OUVERTE;
     card.purge_at = this.purgeAt(card.type.retention_days, card.statut);
     await this.cardsRepo.save(card);
-    return this.toDto(await this.loadCard(cardId), userId);
+    const full = await this.loadCard(cardId);
+    const dtoOut = this.toDto(full, userId);
+    this.emitAudience(full, 'card.updated', dtoOut);
+    return dtoOut;
   }
 
   async supprimer(
@@ -285,6 +299,7 @@ export class CardsService {
     if (card.cree_par !== userId) {
       throw new ForbiddenException('Seul le créateur peut supprimer cette carte');
     }
+    const audienceIds = await this.audienceUserIds(card);
     if (card.id_absence) {
       const absStatut =
         card.statut === CardInstanceStatutType.TRAITEE
@@ -300,6 +315,27 @@ export class CardsService {
       void absStatut;
     }
     await this.cardsRepo.delete({ id: cardId });
+    this.realtime.emitToUsers(audienceIds, 'card.deleted', cardId, {
+      id: cardId,
+    });
+  }
+
+  private emitAudience(
+    card: CardInstance,
+    event: 'card.created' | 'card.updated' | 'response.added',
+    data: unknown,
+  ): void {
+    const ids = (card.audience ?? []).map((a) => a.id_utilisateur);
+    if (ids.length === 0) return;
+    this.realtime.emitToUsers(ids, event, card.id, data);
+  }
+
+  private async audienceUserIds(card: CardInstance): Promise<string[]> {
+    if (card.audience?.length) {
+      return card.audience.map((a) => a.id_utilisateur);
+    }
+    const rows = await this.audienceRepo.find({ where: { id_card: card.id } });
+    return rows.map((r) => r.id_utilisateur);
   }
 
   private mapAbsenceType(typeCode: string): TypeAbsenceGardeType {