feat(infra): add traefik-network-connector; dawarich off shared bridge
- new stack traefik-network-connector: attaches atlas traefik to networks
of containers labelled traefik.enable=true (obeone/traefik_network_connector)
- dawarich: rewrite to upstream compose style (private dawarich network,
no default-bridge sharing, no legacy links). Keep pinned image tags,
host port 3007 (pangolin/newt target), photon override, concurrency 10.
RAILS_ENV development -> production (+ SECRET_KEY_BASE, upstream default).