polkit agent: polkit-gnome is orphaned/EPEL-only on F44; use polkit-kde

VM run failed: 'No match for argument: polkit-gnome'. polkit-gnome is
orphaned in Fedora (EPEL9 only). polkit-kde 6.6.4 is in F44 and ships its
agent's /etc/xdg/autostart .desktop itself, so the manual symlink wiring
is gone too — installing the package is the whole fix.

lib/session.sh

@@ -82,24 +82,14 @@ write_x11_session() {
 
 # Common login-time plumbing every Wayland compositor wants on a bare install.
 install_session_prereqs() {
+    # polkit-kde ships the agent AND its /etc/xdg/autostart .desktop itself —
+    # no manual wiring needed. (polkit-gnome is orphaned, EPEL-only: not on F44,
+    # which is why the first attempt failed with "No match for argument".)
     install_packages \
         xdg-desktop-portal \
         polkit \
-        polkit-gnome \
+        polkit-kde \
         pipewire \
         pipewire-pulseaudio \
         wireplumber
-
-    # A bare compositor (niri, MangoWC, Hyprland) has NO polkit agent: without
-    # one, anything needing privilege elevation (virt-manager's libvirt access,
-    # disks, network settings) fails with "no polkit agent available to
-    # authenticate". Autostart it for every graphical session via the XDG
-    # autostart dir the session runs.
-    local autostart="${XDG_AUTOSTART_DIR:-/etc/xdg/autostart}"
-    local desktop_src="${POLKIT_AGENT_DESKTOP:-/usr/share/applications/polkit-gnome-authentication-agent-1.desktop}"
-    if [[ -f "$desktop_src" ]] && [[ ! -e "$autostart/$(basename "$desktop_src")" ]]; then
-        info "Enabling polkit agent for compositor sessions..."
-        sudo mkdir -p "$autostart"
-        sudo ln -sf "$desktop_src" "$autostart/$(basename "$desktop_src")"
-    fi
 }