git-worktree-switcher: add package option

    shell:

    if (shell == "fish") then

      ''

        ${lib.getExe pkgs.git-worktree-switcher} init ${shell} | source

        ${lib.getExe cfg.package} init ${shell} | source

      ''

    else

      ''

        eval "$(${lib.getExe pkgs.git-worktree-switcher} init ${shell})"

        eval "$(${lib.getExe cfg.package} init ${shell})"

      '';

in

{

  options = {

    programs.git-worktree-switcher = {

      enable = lib.mkEnableOption "git-worktree-switcher, switch between git worktrees with speed.";

      package = lib.mkPackageOption pkgs "git-worktree-switcher" { };

    };

  };