feat(observability): add metrics and monitoring for all 15 backends

- Add MetricsModule to 8 backends missing it (photos, zitare, mukke,
  planta, picture, storage, presi, nutriphi)
- Enable Prometheus scraping for all 15 backends in prometheus.yml
  (was only 6, with 3 commented out and 6 missing entirely)
- Update ServiceDown alert rule to cover all 15 backends
- Update Grafana dashboards (backends, master-overview, system-overview)
  with all backend services in health panels
- Fix imprecise regex in application-details dashboard

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/nutriphi/apps/backend/package.json

@@ -27,6 +27,7 @@
 		"@nutriphi/shared": "workspace:*",
 		"@manacore/shared-nestjs-auth": "workspace:*",
 		"@manacore/shared-nestjs-health": "workspace:*",
+		"@manacore/shared-nestjs-metrics": "workspace:*",
 		"@manacore/shared-nestjs-setup": "workspace:*",
 		"@google/generative-ai": "^0.21.0",
 		"@nestjs/common": "^10.4.15",

apps/nutriphi/apps/backend/src/app.module.ts

@@ -2,6 +2,7 @@ import { Module } from '@nestjs/common';
 import { ConfigModule } from '@nestjs/config';
 import { DatabaseModule } from './db/database.module';
 import { HealthModule } from '@manacore/shared-nestjs-health';
+import { MetricsModule } from '@manacore/shared-nestjs-metrics';
 import { MealModule } from './meal/meal.module';
 import { GoalsModule } from './goals/goals.module';
 import { FavoritesModule } from './favorites/favorites.module';
@@ -17,6 +18,10 @@ import { RecommendationsModule } from './recommendations/recommendations.module'
 		}),
 		DatabaseModule,
 		HealthModule.forRoot({ serviceName: 'nutriphi-backend' }),
+		MetricsModule.register({
+			prefix: 'nutriphi_',
+			excludePaths: ['/health'],
+		}),
 		MealModule,
 		GoalsModule,
 		FavoritesModule,