Add releases download link to README

Author: roman-gmk

README.md

@@ -13,6 +13,13 @@ floating overlay button, android auto screen off, double-DIN screen lock, car st
 
 ---
 
+## Download
+
+Grab the latest APK from [Releases](https://github.com/MelchnerRoman/SleepButton/releases/latest) —
+no need to build it yourself. Sideload it (enable "install from unknown sources" if prompted).
+
+---
+
 ## Features
 - **Floating moon button** – always visible, overlays every app
 - **Drag & snap** – drag anywhere, snaps to left/right edge on release