pub fn resolve_to_ips(hostname: &str) -> Vec<IpAddr>Expand description
Resolve a hostname to a Vec<IpAddr>, with an IP-literal fast path.
If hostname parses as an IP literal, returns vec![that_ip]
without touching the worker pool or the cache. Otherwise falls
back to resolve(hostname) and parses each returned string.
This is the preferred entry point for any caller that’s going to
build SocketAddrs from the result (TCP connect, UDP send-to,
HTTP SSRF validation). Returns an empty Vec on resolution failure.