owenvanvooren/keysight ? reverse-engineered prompt

Build me a simple macOS app that helps light up the bottom of the screen like a fake keyboard light for a MacBook with no backlight.

It should show a bright white bar along the bottom edge of the display, and when the mouse cursor gets close to that bar it should make a soft halo around the pointer so it is easier to see and click things like the Dock and other UI controls. Keep it lightweight, always ready in the background, and make it feel like a small utility rather than a full app. I want it to work nicely on macOS and be easy to build and run in Xcode.

Please make the behavior smooth and subtle, with the lighting effect only appearing when needed. If there are any current macOS specifics I should follow, look up the latest docs online if you need to.