Listen on HOST and PORT instead of a bind address (#666)

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

crates-server/yaak-web/tests/router.rs

@@ -9,7 +9,9 @@ use yaak_web::{Config, router};
 
 fn config(serve: Option<PathBuf>) -> Config {
     Config {
-        bind: "127.0.0.1:0".parse().unwrap(),
+        host: "127.0.0.1".to_string(),
+        port: 0,
+        app_port: None,
         serve,
         allow_private_networks: false,
         allowed_origins: vec!["*".into()],