* fix listening on IPv6 addresses: use net.JoinHostPort
Commit 1e18afb5c862d62be130d563785de5c58f08ae8e broke my caddy setup.
This commit fixes it.
* Refactor solution; simplify, add descriptive comment
* Move network to host, not copy
Co-authored-by: Matthew Holt <mholt@users.noreply.github.com>