feat: add configurable listen port

src/main.rs

@@ -2,7 +2,7 @@ fn main() {
     use soulseek_rs::{Client, PeerAddress};
     use std::time::Duration;
 
-    let mut client = Client::new(
+    let mut client = Client::with_defaults(
         // PeerAddress::new(String::from("server.slsknet.org"), 2242),
         PeerAddress::new(String::from("127.0.0.1"), 2242),
         String::from("insane_in_the_brain3"),