don't return (buffer, searchList) tuple when building search list, but only return search list itself. (No point returning buffer as it is never modified or moved.)

shell/search-thread.sml

@@ -6,7 +6,7 @@ struct
   fun loop (searchMailbox, inputMailbox) =
     let
       val (buffer, searchString) = Mailbox.recv searchMailbox
-      val (_, searchList) = SearchList.build (buffer, searchString)
+      val searchList = SearchList.build (buffer, searchString)
       val () = Mailbox.send (inputMailbox, InputMsg.WITH_SEARCH_LIST searchList)
     in
       loop (searchMailbox, inputMailbox)