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.spec.ts

@@ -2,6 +2,7 @@ import { Test, TestingModule } from '@nestjs/testing';
 import { getRepositoryToken } from '@nestjs/typeorm';
 import { ForbiddenException } from '@nestjs/common';
 import { CardsService } from './cards.service';
+import { CardsRealtimeService } from './cards-realtime.service';
 import { AbsencesGardeService } from '../absences-garde/absences-garde.service';
 import { CardType, CardResponseModeType } from 'src/entities/card_types.entity';
 import {
@@ -32,6 +33,7 @@ describe('CardsService (#194)', () => {
     create: jest.fn((x) => x),
     save: jest.fn(),
     findOne: jest.fn(),
+    find: jest.fn(),
   };
   const responsesRepo = {
     create: jest.fn((x) => x),
@@ -44,6 +46,7 @@ describe('CardsService (#194)', () => {
     maj: jest.fn(),
     supprimer: jest.fn(),
   };
+  const realtime = { emitToUsers: jest.fn() };
 
   beforeEach(async () => {
     const module: TestingModule = await Test.createTestingModule({
@@ -56,6 +59,7 @@ describe('CardsService (#194)', () => {
         { provide: getRepositoryToken(AmChildren), useValue: amChildrenRepo },
         { provide: getRepositoryToken(ParentsChildren), useValue: parentsChildrenRepo },
         { provide: AbsencesGardeService, useValue: absencesService },
+        { provide: CardsRealtimeService, useValue: realtime },
       ],
     }).compile();
     service = module.get(CardsService);
@@ -112,7 +116,11 @@ describe('CardsService (#194)', () => {
         retention_days: 14,
       },
       responses: [],
-      audience: [],
+      audience: [
+        { id_utilisateur: 'am-1' },
+        { id_utilisateur: 'p-1' },
+        { id_utilisateur: 'p-2' },
+      ],
     });
 
     const res = await service.creer('am-1', RoleType.ASSISTANTE_MATERNELLE, {
@@ -124,6 +132,12 @@ describe('CardsService (#194)', () => {
 
     expect(absencesService.creer).toHaveBeenCalled();
     expect(audienceRepo.save).toHaveBeenCalled();
+    expect(realtime.emitToUsers).toHaveBeenCalledWith(
+      ['am-1', 'p-1', 'p-2'],
+      'card.created',
+      'card-1',
+      expect.any(Object),
+    );
     expect(res.type_code).toBe('conge_am');
     expect(res.statut).toBe(CardInstanceStatutType.OUVERTE);
   });