Support passing files and directories as arguments to nixfmt-plus script

home-manager/_mixins/scripts/nixfmt-plus/nixfmt-plus.sh

@@ -1,5 +1,14 @@
 #!/usr/bin/env bash
+set -eou pipefail
 
-deadnix --edit
-statix fix
-nixfmt --verify .
+if [ $# -eq 0 ]; then
+  deadnix --edit
+  statix fix
+  nixfmt --verify .
+else
+  deadnix --edit "$@"
+  for target in "$@"; do
+    statix fix -- "$target"
+  done
+  nixfmt --verify "$@"
+fi