Explain which menu bar items can be hidden

Hiding other apps' icons worked, but Apple pins Spotlight, Clock, Battery
and Control Center to the right of the menu bar, so a third-party item can
never be placed after them to push them away. Document the real limit so
the behaviour is not mistaken for a bug.

💘 Generated with Crush

Assisted-by: Crush:deepseek-v4.1-flash

build-app.sh

@@ -2,7 +2,7 @@
 set -euo pipefail
 cd "$(dirname "$0")"
 
-VERSION="${1:-0.2.2}"
+VERSION="${1:-0.2.3}"
 
 swift build -c release