Move docker-compose.yaml to the repo root and add docker-compose.prod.yaml
that stands up a Caddy 2 sidecar on 80/443 proxying to the fabro service
on 32276 (the CLI's default port). Auto-HTTPS is handled by Caddy when
FABRO_DOMAIN is set; certs persist in named volumes.
Switch the container's internal listener from 80 to 32276, which lets us
drop libcap2-bin and the CAP_NET_BIND_SERVICE file capability.
