Add app icon and update build process

convert_icon.py

@@ -0,0 +1,17 @@
+from PIL import Image
+import os
+
+def convert_to_ico(png_path, ico_path):
+    if not os.path.exists(png_path):
+        print(f"Error: {png_path} not found.")
+        return
+
+    try:
+        img = Image.open(png_path)
+        img.save(ico_path, format='ICO', sizes=[(256, 256), (128, 128), (64, 64), (48, 48), (32, 32), (16, 16)])
+        print(f"Successfully converted {png_path} to {ico_path}")
+    except Exception as e:
+        print(f"Error converting image: {e}")
+
+if __name__ == "__main__":
+    convert_to_ico("app_icon.png", "app_icon.ico")