Integrates https://github.com/outis1one/easy-asterisk into the post-install
system. Downloads the management script and coturn entrypoint at install time,
generates docker-compose.yml with host-networking Asterisk + coturn, writes
a randomised TURN password, and opens UFW ports for SIP/RTP/TURN.
Interactive FQDN setup chooses between LAN-only (UDP, no TLS) and FQDN mode
(TLS+SRTP+TURN) and prints required router port-forward instructions.
https://claude.ai/code/session_014CCYqVwW6d6f5dw1qRokYt