Zeta Mode and hosts.env

The --zeta option enables host-per-service mode. BrowserBox then expects:

~/.config/dosaygo/bbpro/hosts.env

At runtime, bbx run reads ADDR_<PORT> from that file to construct the login link for the main service port.

Use zeta mode when:

• nginx is doing hostname-based proxying

• you want separate hostnames per BrowserBox service

• you want clean standard-port edge routing

If hosts.env is missing, bbx run fails fast in zeta mode.