Add Gradio auth: login required via APP_USERNAME/APP_PASSWORD env vars

app.py

@@ -398,4 +398,7 @@ with gr.Blocks(title="SAM 3 Asset Extractor") as demo:
     submit_btn.click(fn=extract_assets, inputs=[input_image], outputs=[output_gallery])
 
 if __name__ == "__main__":
-    demo.launch(css=custom_css, theme=app_theme)
+    # Auth via HF Space secrets (Settings → Variables and Secrets)
+    auth_user = os.environ.get("APP_USERNAME", "veurone")
+    auth_pass = os.environ.get("APP_PASSWORD", "sam3extract")
+    demo.launch(css=custom_css, theme=app_theme, auth=(auth_user, auth_pass))