LinScreen v14.0.1

Desktop integration fix release.

Fixed

Debian package now configures CMake with /usr as install prefix.
Desktop launcher and DBus service now point to /usr/bin/linscreen.
GNOME/KDE can discover org.linscreen.LinScreen.desktop for portal app registration.
Debian maintainer scripts refresh desktop, icon, and KDE service caches after install/removal.
Automatic update checks remain disabled in Debian builds until the release endpoint is live.