fix: format.nu path self

Author: blindFS

format.nu

@@ -1,5 +1,7 @@
 #!/usr/bin/env nu --stdin
 
+const script_path = path self .
+
 # Helper to run topiary with the correct environment variables for topiary-nushell
 @example "Read from stdin" { bat foo.nu | format.nu }
 @example "Format files (in-place replacement)" { format.nu foo.nu bar.nu }
@@ -8,7 +10,7 @@ def main [
   --config_dir (-c): path # Root of the topiary-nushell repo, defaults to the parent directory of this script
   ...files: path # Files to format
 ]: [nothing -> nothing string -> string] {
-  let config_dir = $config_dir | default (pwd)
+  let config_dir = $config_dir | default $script_path
   $env.TOPIARY_CONFIG_FILE = ($config_dir | path join languages.ncl)
   $env.TOPIARY_LANGUAGE_DIR = ($config_dir | path join languages)