changelogen: add update script (#461235)

pkgs/by-name/ch/changelogen/package.nix

@@ -5,6 +5,7 @@
   nodejs,
   pnpm_10,
   npmHooks,
+  nix-update-script,
 }:
 let
   pnpm = pnpm_10;
@@ -42,6 +43,8 @@ stdenv.mkDerivation (finalAttrs: {
 
   dontNpmPrune = true;
 
+  passthru.updateScript = nix-update-script { };
+
   meta = {
     description = "Beautiful Changelogs using Conventional Commits";
     homepage = "https://github.com/unjs/changelogen";