fix: else claude message

Signed-off-by: Sachin Beniwal <s474996633@gmail.com>

Author: benodiwal

src/dune_sexp/versioned_file.ml

@@ -64,7 +64,11 @@ struct
           let has_non_ascii = String.exists ver ~f:(fun c -> Char.code c >= 128) in
           if has_non_ascii
           then User_error.raise ~loc:ver_loc [ Pp.text Atom.non_ascii_error_message ]
-          else User_error.raise ~loc:ver_loc [ Pp.textf "Invalid atom: %S" ver ]
+          else
+            User_error.raise
+              ~loc:ver_loc
+              [ Pp.text "Invalid version. Version must be two numbers separated by a dot."
+              ]
       in
       let dune_lang_ver =
         Decoder.parse Syntax.Version.decode Univ_map.empty (Atom (ver_loc, ver_atom))