feat: persistent payload storage and automated db migrations

docker-compose.yml

@@ -12,6 +12,8 @@ services:
     environment:
       POSTGRES_URI: postgres://${PAYLOAD_DB_USER:-payload}:${PAYLOAD_DB_PASSWORD:-120in09oenaoinsd9iaidon}@klz-db:5432/${PAYLOAD_DB_NAME:-payload}
       PAYLOAD_SECRET: ${PAYLOAD_SECRET:-fallback-secret-for-production-needs-change}
+    volumes:
+      - klz_media_data:/app/public/media
     labels:
       - "traefik.enable=true"
       # HTTP ⇒ HTTPS redirect
@@ -89,3 +91,5 @@ networks:
 volumes:
   klz_db_data:
     external: false
+  klz_media_data:
+    external: false