debug: add traceback visualizer on error

app.py

@@ -33,11 +33,19 @@ def process_faceless(input_image, prompt="", negative_prompt=""):
         else:
             return lineart_path, None
     except Exception as e:
-        print(f"[ERRO] process_faceless: {e}")
-        # Save original to temp file to be safe
-        orig_path = os.path.join(tempfile.gettempdir(), f"orig_{os.getpid()}.png")
-        input_image.save(orig_path, "PNG")
-        return orig_path, None
+        import traceback
+        err_str = "".join(traceback.format_exception(type(e), e, e.__traceback__))
+        print(f"[ERRO] process_faceless: {err_str}")
+        
+        from PIL import ImageDraw
+        err_img = Image.new("RGBA", (1024, 1024), (40, 0, 0, 255))
+        draw = ImageDraw.Draw(err_img)
+        draw.text((10, 10), err_str, fill=(255, 255, 255, 255))
+        
+        err_path = os.path.join(tempfile.gettempdir(), f"err_{os.getpid()}_{os.urandom(4).hex()}.png")
+        err_img.save(err_path, "PNG")
+        return err_path, None
+
 
 # Interface Gradio
 demo = gr.Interface(