lock-fancy-rapid: add meta.mainProgram; format (#355172)

{ lib, stdenv, fetchFromGitHub, xorg, i3lock }:

{

  lib,

  stdenv,

  fetchFromGitHub,

  xorg,

  i3lock,

}:

stdenv.mkDerivation {

  pname = "i3lock-fancy-rapid";

    description = "Faster implementation of i3lock-fancy";

    homepage = "https://github.com/yvbbrjdr/i3lock-fancy-rapid";

    maintainers = with maintainers; [ nickhu ];

    mainProgram = "i3lock-fancy-rapid";

    license = licenses.bsd3;

    platforms = platforms.linux;

  };