fixed compound commands not working in pipelines

improved pipe assignment logic to prevent potential resource leaks

src/readline/mod.rs

@@ -639,6 +639,10 @@ impl ShedVi {
             .update_pending_cmd((self.editor.as_str(), self.editor.cursor.get()));
           let hint = self.history.get_hint();
           self.editor.set_hint(hint);
+
+          // If we are here, we hit a case where pressing tab returned a single candidate
+          // So we can just go ahead and reset the completer after this
+          self.completer.reset();
         }
         Ok(None) => {
           let post_cmds = read_logic(|l| l.get_autocmds(AutoCmdKind::OnCompletionStart));