Adjust defaults and preset handling

- Switch startup_preset to default key
- Add built-in on/off presets and tweak device defaults

Made-with: Cursor

src/settings.py

@@ -13,14 +13,14 @@ class Settings(dict):
 
     def set_defaults(self):
         self["led_pin"] = 10
-        self["num_leds"] = 50
+        self["num_leds"] = 119
       
         self["color_order"] = "rgb"
-        self["name"] = f"led-{ubinascii.hexlify(network.WLAN(network.AP_IF).config('mac')).decode()}"
+        self["name"] = "a"
        
         self["debug"] = False
-        self["default"] = None
-        self["brightness"] = 255
+        self["default"] = "on"
+        self["brightness"] = 32
 
     def save(self):
         try: