fix(infra): add coolify network to db and redis services

Garante que db e redis entram na rede coolify ao serem recriados,
permitindo que novos deploys via Coolify resolvam os hostnames.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docker-compose.prod.yml

@@ -25,6 +25,7 @@ services:
       retries: 10
     networks:
       - arcadia-internal
+      - coolify
 
   # ── Redis ────────────────────────────────────────────────────────────────────
   redis:
@@ -35,6 +36,7 @@ services:
       - redis_data:/data
     networks:
       - arcadia-internal
+      - coolify
 
   # ── App principal ─────────────────────────────────────────────────────────
   app: