clarified names;

--- a/src/Pure/Tools/scala_build.scala	Tue Jul 12 14:38:31 2022 +0200
+++ b/src/Pure/Tools/scala_build.scala	Tue Jul 12 14:40:41 2022 +0200
@@ -105,9 +105,9 @@
           val jar_name =
             result.jar_path match {
               case Some(path) => path.file_name
-              case None => "result.jar"
+              case None => "scala_build.jar"
             }
-          List(Bytes("scala_build/" + jar_name), result.jar_bytes, Bytes(result.output))
+          List(Bytes("classpath/" + jar_name), result.jar_bytes, Bytes(result.output))
         case _ => error("Bad arguments")
       }
   }