Add power settings for the lighting, bump to 1.4.0

New Power page:
- toggle for the firmware's 30 s keyboard backlight timeout
- idle timeout for keyboard and lightbar, separately for AC and battery;
  predatord watches all input devices and restores the lighting on the
  next input
- battery rules: dimmed keyboard brightness, keyboard off, lightbar off

The rules only change what is sent to the hardware; the saved lighting
settings stay untouched.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

plasmoid/org.predatorcontrol.panel/metadata.json

@@ -12,7 +12,7 @@
         "Id": "org.predatorcontrol.panel",
         "License": "GPL-2.0-only",
         "Name": "Predator Control",
-        "Version": "1.3.0",
+        "Version": "1.4.0",
         "Website": "https://git.mrblake.cc/MrBlake/Cachy-Predator-Keyboard"
     },
     "X-Plasma-API-Minimum-Version": "6.0",