feat(infra) : add logs volume to prod docker-compose

Persist var/log/ via named volume coltura_logs so logs survive
container restarts.

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

infra/prod/docker-compose.prod.yml

@@ -7,6 +7,10 @@ services:
       - "8086:80"
     volumes:
       - ./config/jwt:/var/www/html/config/jwt:ro
+      - coltura_logs:/var/www/html/var/log
     extra_hosts:
       - "host.docker.internal:host-gateway"
     restart: unless-stopped
+
+volumes:
+  coltura_logs: