Add led pin in settings

src/settings.py

@@ -11,6 +11,7 @@ class Settings(dict):
         self.load()  # Load settings from file during initialization
 
     def set_defaults(self):
+        self["led_pin"] = 10
         self["num_leds"] = 50
         self["pattern"] = "on"
         self["color1"] = "#00ff00"