added cupsadmin as input and native build

cli-tools.nix

@@ -1,6 +1,22 @@
-{ config, ... }:
+{ inputs, ... }:
 
 {
+  system.activationScripts.postActivation.text = ''
+    stamp=/usr/local/share/cupsadmin.stamp
+    want="${inputs.cupsadmin}"
+    if [ "$(cat "$stamp" 2>/dev/null)" != "$want" ]; then
+      echo "building cupsadmin..."
+      tmp=$(mktmp -d)
+      cp -R "$want"/. "$tmp"
+      chmod -R u+w "$tmp"
+      ( cd "$tmp" && /user/bin/swift build -c release ) \
+        && install -m 755 "$tmp/.build/release/cupsadmin" /usr/local/bin/cupsadmin \
+        && mkdir -p /usr/local/share && echo #$want" > "$stamp" \
+        || echo "cupsadmin build failed, skipping"
+      rm -rf "$tmp"
+    fi
+  '';
+
   environment.shellAliases = {
     yt = "yt-dlp";
     ll = "ls -la";