nixos/hardware/nvidia: add prime.offload.offloadCmdMainProgram (#407588)

      prime.offload.enableOffloadCmd = lib.mkEnableOption ''

        adding a `nvidia-offload` convenience script to {option}`environment.systemPackages`

        for offloading programs to an nvidia device. To work, should have also enabled

        for offloading programs to an nvidia device. To work, you must also enable

        {option}`hardware.nvidia.prime.offload.enable` or {option}`hardware.nvidia.prime.reverseSync.enable`.

        Example usage `nvidia-offload sauerbraten_client`

        Example usage: `nvidia-offload sauerbraten_client`

        This script can be renamed with {option}`hardware.nvidia.prime.offload.enableOffloadCmd`.

      '';

      prime.offload.offloadCmdMainProgram = lib.mkOption {

        type = lib.types.str;

        description = ''

          Specifies the CLI name of the {option}`hardware.nvidia.prime.offload.enableOffloadCmd`

          convenience script for offloading programs to an nvidia device.

        '';

        default = "nvidia-offload";

        example = "prime-run";

      };

      prime.reverseSync.enable = lib.mkEnableOption ''

        NVIDIA Optimus support using the NVIDIA proprietary driver via reverse

            lib.optional cfg.nvidiaSettings nvidia_x11.settings

            ++ lib.optional cfg.nvidiaPersistenced nvidia_x11.persistenced

            ++ lib.optional offloadCfg.enableOffloadCmd (

              pkgs.writeShellScriptBin "nvidia-offload" ''

              pkgs.writeShellScriptBin cfg.prime.offload.offloadCmdMainProgram ''

                export __NV_PRIME_RENDER_OFFLOAD=1

                export __NV_PRIME_RENDER_OFFLOAD_PROVIDER=NVIDIA-G0

                export __GLX_VENDOR_LIBRARY_NAME=nvidia