fix: use devUrl when dev (#556)

src-tauri/src/lib.rs

@@ -21,8 +21,17 @@ pub fn run() {
         .plugin(tauri_plugin_localhost::Builder::new(port).build())
         .plugin(tauri_plugin_window_state::Builder::default().build())
         .setup(move |app| {
-            let url = format!("http://localhost:{}", port).parse().unwrap();
-            let window_url = WebviewUrl::External(url);
+            // Dev: use devUrl from tauri.conf.json (http://localhost:8080) to support HMR
+            #[cfg(debug_assertions)]
+            let window_url = WebviewUrl::App(Default::default());
+
+            // Release: tauri-plugin-localhost serves bundled frontend assets on this port
+            #[cfg(not(debug_assertions))]
+            let window_url = {
+                let url = format!("http://localhost:{}", port).parse().unwrap();
+                WebviewUrl::External(url)
+            };
+
             WebviewWindowBuilder::new(app, "main".to_string(), window_url)
                 .title("Cinny")
                 .build()?;