fix(frontend): aligne le modèle Alert et AlertsService sur le contrat /alerts

Le modèle front portait un alert_id texte, des value/threshold non nullables et
ignorait metric et prediction_id, alors que l'API sérialise un entier, des
flottants nullables et ces deux champs. Toute comparaison avec l'alert_id d'une
recommandation échouait silencieusement.

- alert.model.ts : alert_id number, value/threshold/metric/prediction_id nullables
- alerts.service.ts : getAlerts(filters) pose site_id et severity en HttpParams,
  les deux filtres que l'API accepte
- alerts.fixture.ts : réaligné sur le contrat (ids entiers, horodatages UTC,
  champs nuls sur outage/sensor, un cas spike)
- alert-presentation.ts : tons, libellés et unités partagés ; low passe en
  neutre, le vert se lisait comme un état sain

apps/frontend/src/app/core/mocks/alerts.fixture.ts

@@ -2,53 +2,63 @@ import { Alert } from '../../shared/models/alert.model';
 
 export const ALERTS_FIXTURE: Alert[] = [
   {
-    alert_id: 'ALR-SITE002-1718458320',
+    alert_id: 5,
-    timestamp: '2026-09-15T11:12:00',
     site_id: 'SITE002',
+    timestamp: '2026-09-15T11:12:00Z',
+    type: 'threshold',
     severity: 'critical',
-    type: 'outage',
+    message: 'Puissance appelée 812.5 kW au-dessus de la capacité du site (720.0 kW)',
-    message: 'Risque de surcharge sur Usine Lyon Vénissieux',
     value: 812.5,
     threshold: 720.0,
+    metric: 'consumption_kw',
+    prediction_id: null,
   },
   {
-    alert_id: 'ALR-SITE003-1718458321',
+    alert_id: 4,
-    timestamp: '2026-09-15T11:05:00',
     site_id: 'SITE003',
+    timestamp: '2026-09-15T11:05:00Z',
+    type: 'outage',
     severity: 'critical',
-    type: 'sensor',
+    message: 'Aucune lecture depuis 5:00:00 (dernière lecture : 2026-09-15T06:05:00+00:00)',
-    message: 'Perte réseau totale sur Data Center Marseille',
+    value: null,
-    value: 0,
+    threshold: null,
-    threshold: 0,
+    metric: null,
+    prediction_id: null,
   },
   {
-    alert_id: 'ALR-SITE005-1718458322',
+    alert_id: 3,
-    timestamp: '2026-09-15T10:47:00',
     site_id: 'SITE005',
+    timestamp: '2026-09-15T10:47:00Z',
+    type: 'spike',
     severity: 'high',
-    type: 'threshold',
+    message: 'Variation brutale entre deux lectures consécutives (260.0 kW -> 410.0 kW)',
-    message: 'Usine Toulouse approche de son seuil de capacité',
     value: 410.0,
-    threshold: 480.0,
+    threshold: 260.0,
+    metric: 'consumption_kw',
+    prediction_id: null,
   },
   {
-    alert_id: 'ALR-SITE006-1718458323',
+    alert_id: 2,
-    timestamp: '2026-09-15T10:30:00',
     site_id: 'SITE006',
-    severity: 'medium',
+    timestamp: '2026-09-15T10:30:00Z',
     type: 'sensor',
-    message: 'Capteur de température défaillant sur Bureau Lille',
+    severity: 'medium',
-    value: 0,
+    message: 'Qualité de mesure degraded (capteur hors ligne, valeur nulle)',
-    threshold: 0,
+    value: null,
+    threshold: null,
+    metric: null,
+    prediction_id: null,
   },
   {
-    alert_id: 'ALR-SITE004-1718458324',
+    alert_id: 1,
-    timestamp: '2026-09-15T09:58:00',
     site_id: 'SITE004',
-    severity: 'low',
+    timestamp: '2026-09-15T09:58:00Z',
     type: 'anomaly',
-    message: 'Comportement de consommation inhabituel sur Bureau Bordeaux',
+    severity: 'low',
+    message: 'Écart de 13% entre la consommation mesurée (62.0 kWh) et la prévision (55.0 kWh)',
     value: 62.0,
     threshold: 55.0,
+    metric: 'consumption_kwh',
+    prediction_id: 42,
   },
 ];

apps/frontend/src/app/core/services/alerts.service.spec.ts

@@ -3,6 +3,20 @@ import { provideHttpClient } from '@angular/common/http';
 import { provideHttpClientTesting, HttpTestingController } from '@angular/common/http/testing';
 import { AlertsService } from './alerts.service';
 import { environment } from '../../../environments/environment';
+import { Alert } from '../../shared/models/alert.model';
+
+const ALERT_API: Alert = {
+  alert_id: 1,
+  site_id: 'site-1',
+  timestamp: '2026-09-16T00:00:00Z',
+  type: 'threshold',
+  severity: 'high',
+  message: 'Dépassement du seuil configuré',
+  value: 812.5,
+  threshold: 720.0,
+  metric: 'consumption_kw',
+  prediction_id: null,
+};
 
 describe('AlertsService', () => {
   let service: AlertsService;
@@ -18,26 +32,35 @@ describe('AlertsService', () => {
 
   afterEach(() => httpMock.verify());
 
-  it("appelle le bon endpoint et retourne un tableau d'alertes", () => {
+  it("appelle le bon endpoint sans paramètre et retourne un tableau d'alertes", () => {
-    let result: unknown;
+    let result: Alert[] = [];
     service.getAlerts().subscribe((r) => (result = r));
 
-    const req = httpMock.expectOne(`${environment.apiUrl}/alerts`);
+    const req = httpMock.expectOne(
-    expect(req.request.method).toBe('GET');
+      (r) => r.url === `${environment.apiUrl}/alerts` && r.method === 'GET',
+    );
+    expect(req.request.params.keys()).toEqual([]);
+    req.flush([ALERT_API]);
 
-    req.flush([
+    expect(result.length).toBe(1);
-      {
+    expect(result[0].alert_id).toBe(1);
-        alert_id: 'ALR-TEST-1',
+    expect(result[0].prediction_id).toBeNull();
-        timestamp: '2026-09-15T12:00:00',
+  });
-        site_id: 'SITE001',
-        severity: 'high',
-        type: 'threshold',
-        message: 'Test',
-        value: 100,
-        threshold: 90,
-      },
-    ]);
 
-    expect((result as unknown[]).length).toBe(1);
+  it('transmet les filtres site_id et severity en paramètres de requête', () => {
+    service.getAlerts({ site_id: 'SITE001', severity: 'high' }).subscribe();
+
+    const req = httpMock.expectOne((r) => r.url === `${environment.apiUrl}/alerts`);
+    expect(req.request.params.get('site_id')).toBe('SITE001');
+    expect(req.request.params.get('severity')).toBe('high');
+    req.flush([]);
+  });
+
+  it('ne pose pas de paramètre pour un filtre omis', () => {
+    service.getAlerts({ site_id: 'SITE001' }).subscribe();
+
+    const req = httpMock.expectOne((r) => r.url === `${environment.apiUrl}/alerts`);
+    expect(req.request.params.has('severity')).toBe(false);
+    req.flush([]);
   });
 });

apps/frontend/src/app/core/services/alerts.service.ts

@@ -1,13 +1,25 @@
 import { Service, inject } from '@angular/core';
-import { HttpClient } from '@angular/common/http';
+import { HttpClient, HttpParams } from '@angular/common/http';
 import { environment } from '../../../environments/environment';
-import { Alert } from '../../shared/models/alert.model';
+import { Alert, AlertSeverity } from '../../shared/models/alert.model';
+
+export interface AlertFilters {
+  site_id?: string;
+  severity?: AlertSeverity;
+}
 
 @Service()
 export class AlertsService {
   private http = inject(HttpClient);
 
-  getAlerts() {
+  getAlerts(filters: AlertFilters = {}) {
-    return this.http.get<Alert[]>(`${environment.apiUrl}/alerts`);
+    let params = new HttpParams();
+    if (filters.site_id) {
+      params = params.set('site_id', filters.site_id);
+    }
+    if (filters.severity) {
+      params = params.set('severity', filters.severity);
+    }
+    return this.http.get<Alert[]>(`${environment.apiUrl}/alerts`, { params });
   }
 }

apps/frontend/src/app/shared/models/alert-presentation.spec.ts

@@ -0,0 +1,37 @@
+import {
+  LIBELLE_PAR_SEVERITE,
+  LIBELLE_PAR_TYPE,
+  SEVERITES,
+  TON_PAR_SEVERITE,
+  TYPES_ALERTE,
+  UNITE_PAR_METRIQUE,
+} from './alert-presentation';
+
+describe('alert-presentation', () => {
+  it('distingue le ton des sévérités high et critical', () => {
+    expect(TON_PAR_SEVERITE.high).toBe('danger');
+    expect(TON_PAR_SEVERITE.critical).toBe('critical');
+    expect(TON_PAR_SEVERITE.high).not.toBe(TON_PAR_SEVERITE.critical);
+  });
+
+  it("n'affiche pas une alerte faible avec le ton de succès", () => {
+    expect(TON_PAR_SEVERITE.low).toBe('neutral');
+    expect(TON_PAR_SEVERITE.medium).toBe('warning');
+  });
+
+  it('donne un libellé français à chaque sévérité et à chaque type', () => {
+    for (const severite of SEVERITES) {
+      expect(LIBELLE_PAR_SEVERITE[severite]).toBeTruthy();
+    }
+    for (const type of TYPES_ALERTE) {
+      expect(LIBELLE_PAR_TYPE[type]).toBeTruthy();
+    }
+    expect(SEVERITES.length).toBe(4);
+    expect(TYPES_ALERTE.length).toBe(5);
+  });
+
+  it('associe une unité à chaque métrique du contrat', () => {
+    expect(UNITE_PAR_METRIQUE.consumption_kw).toBe('kW');
+    expect(UNITE_PAR_METRIQUE.consumption_kwh).toBe('kWh');
+  });
+});

apps/frontend/src/app/shared/models/alert-presentation.ts

@@ -0,0 +1,41 @@
+import { BadgeTone } from '../components/ui/badge/badge';
+import { AlertMetric, AlertSeverity, AlertType } from './alert.model';
+
+// Pourquoi : `low` en neutre plutôt qu'en vert, une alerte faible reste une alerte ; le vert se
+// lisait comme « tout va bien » à côté des rouges.
+export const TON_PAR_SEVERITE: Record<AlertSeverity, BadgeTone> = {
+  low: 'neutral',
+  medium: 'warning',
+  high: 'danger',
+  critical: 'critical',
+};
+
+export const LIBELLE_PAR_SEVERITE: Record<AlertSeverity, string> = {
+  low: 'Faible',
+  medium: 'Moyenne',
+  high: 'Élevée',
+  critical: 'Critique',
+};
+
+export const LIBELLE_PAR_TYPE: Record<AlertType, string> = {
+  spike: 'Pic de consommation',
+  threshold: 'Seuil dépassé',
+  anomaly: 'Anomalie',
+  outage: 'Coupure',
+  sensor: 'Capteur',
+};
+
+export const UNITE_PAR_METRIQUE: Record<AlertMetric, string> = {
+  consumption_kw: 'kW',
+  consumption_kwh: 'kWh',
+};
+
+export const SEVERITES: readonly AlertSeverity[] = ['low', 'medium', 'high', 'critical'];
+
+export const TYPES_ALERTE: readonly AlertType[] = [
+  'spike',
+  'threshold',
+  'anomaly',
+  'outage',
+  'sensor',
+];

apps/frontend/src/app/shared/models/alert.model.ts

@@ -1,13 +1,16 @@
 export type AlertSeverity = 'low' | 'medium' | 'high' | 'critical';
 export type AlertType = 'spike' | 'threshold' | 'anomaly' | 'outage' | 'sensor';
+export type AlertMetric = 'consumption_kw' | 'consumption_kwh';
 
 export interface Alert {
-  alert_id: string;
+  alert_id: number;
-  timestamp: string;
   site_id: string;
-  severity: AlertSeverity;
+  timestamp: string;
   type: AlertType;
+  severity: AlertSeverity;
   message: string;
-  value: number;
+  value: number | null;
-  threshold: number;
+  threshold: number | null;
+  metric: AlertMetric | null;
+  prediction_id: number | null;
 }