feat(proxy-engine): add Rust-based outbound calling, WebRTC bridging, and voicemail handling

rust/crates/proxy-engine/src/config.rs

@@ -14,8 +14,18 @@ pub struct Endpoint {
 }
 
 impl Endpoint {
+    /// Resolve to a SocketAddr. Handles both IP addresses and hostnames.
     pub fn to_socket_addr(&self) -> Option<SocketAddr> {
-        format!("{}:{}", self.address, self.port).parse().ok()
+        // Try direct parse first (IP address).
+        if let Ok(addr) = format!("{}:{}", self.address, self.port).parse() {
+            return Some(addr);
+        }
+        // DNS resolution for hostnames.
+        use std::net::ToSocketAddrs;
+        format!("{}:{}", self.address, self.port)
+            .to_socket_addrs()
+            .ok()
+            .and_then(|mut addrs| addrs.next())
     }
 }