feat(moonarch-git): ship camera unit (pkgrel 17)

moonarch-camera.service switches all cameras off on boot. System units are
installed file by file here, so a new one needs its own install line; the
enable is hardware-gated in post_install, like the batsaver service.

The four moonarch-camera-* scripts and the quickshell components need no
packaging change — they are covered by the defaults/bin glob and the
defaults/xdg find loop.

moonarch-git/PKGBUILD

@@ -5,7 +5,7 @@
 
 pkgname=moonarch-git
 pkgver=r157.7568fe2
-pkgrel=16
+pkgrel=17
 pkgdesc="Moonarch desktop environment defaults — Niri, Waybar, Catppuccin Mocha"
 arch=('any')
 url="https://gitea.moonarch.de/nevaforget/moonarch"
@@ -242,6 +242,10 @@ package() {
     install -Dm644 defaults/etc/systemd/system/moonarch-batsaver.service \
         "$pkgdir/usr/lib/systemd/system/moonarch-batsaver.service"
 
+    # --- Systemd system service (switch all cameras off on boot) -> /usr/lib/systemd/system/ ---
+    install -Dm644 defaults/etc/systemd/system/moonarch-camera.service \
+        "$pkgdir/usr/lib/systemd/system/moonarch-camera.service"
+
 }
 
 backup=(

moonarch-git/moonarch.install

@@ -74,6 +74,11 @@ post_install() {
         systemctl enable moonarch-batsaver.service 2>/dev/null || true
     fi
 
+    # Cameras off after every boot — only on machines that have one
+    if ls /sys/class/video4linux/video* >/dev/null 2>&1; then
+        systemctl enable moonarch-camera.service 2>/dev/null || true
+    fi
+
     echo "==> Moonarch defaults installed."
     echo "==> For first-time setup run: /opt/moonarch/scripts/post-install.sh"
     echo "==> This enables services and configures firewall."