fix: merge monitoring into main docker-compose.yml

All services (app + Prometheus + Grafana + node-exporter + cAdvisor)
are now in a single docker-compose.yml. One `docker compose up -d`
starts everything. No more separate monitoring file needed.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

.gitea/workflows/deploy.yml

@@ -66,10 +66,6 @@ jobs:
             echo "=== Deploy summary ==="
             docker compose ps
             echo "Health: $(curl -sf http://localhost:8001/health 2>/dev/null || echo 'FAILED')"
-
-            echo "=== Starting monitoring ==="
-            docker compose -f docker-compose.yml -f docker-compose.monitoring.yml up -d prometheus grafana node-exporter cadvisor || true
-            docker compose -f docker-compose.yml -f docker-compose.monitoring.yml ps || true
           ENDSSH
 
       - name: Wait for frontend