Add the Ansible README and expand prod bootstrap coverage for StorageBox keys, DB labels, DB stack configuration, and act runner setup. Update MongoDB configuration for replica set support and refresh prod roadmap/setup documentation for Swarm labels, StorageBox-backed cert paths, and recovery guidance.
- Database nodes now join the Docker Swarm as workers with `role=db` labels, allowing Swarm to manage their dedicated services.
- The `docker-stack-infra.yml` has been updated for production to focus solely on application-level infrastructure components.
- Dedicated database services (PostgreSQL, MongoDB, Patroni-etcd) are now explicitly deployed in separate Swarm stacks on `iklim-db-XX` nodes.
- Standardizes node naming conventions (`iklim-app-XX`, `iklim-db-XX`) across the production roadmap documentation.
- Clarifies that the `etcd` service within `docker-stack-infra.yml` is exclusively for APISIX configuration, distinct from Patroni's etcd cluster.
