feat: implement openExternalUrl utility for consistent external link handling

src/app/utils/tauri.ts

@@ -1,3 +1,19 @@
+/**
+ * Open an external URL using Tauri shell on desktop/mobile, or window.open in browser
+ * @param url The URL to open
+ */
+export const openExternalUrl = async (url: string): Promise<void> => {
+  if (isTauri()) {
+    try {
+      const { open } = await import('@tauri-apps/plugin-shell');
+      await open(url);
+      return;
+    } catch (err) {
+      console.warn('Tauri shell.open failed, falling back to window.open:', err);
+    }
+  }
+  window.open(url, '_blank');
+};
 /**
  * Tauri-specific utilities for desktop and mobile platforms
  */