this is purely a rebase of our branch onto the latest jetpack-nixos

On downstream side the nixpkgs with cuda causing issues. So I'll test it with rebased nixpkgs.

When used with cuda there is mismatch between nixpkgs and jetpack-nixos :

    262|       fargs = functionArgs f;

   error: path '/nix/store/g02rq8ap30x3fp8zrz07ip5v1s0pzidn-source/pkgs/development/cuda-modules/packages/backendStdenv.nix' does not exist

When used with cuda there is mismatch between nixpkgs and jetpack-nixos :

    262|       fargs = functionArgs f;

   error: path '/nix/store/g02rq8ap30x3fp8zrz07ip5v1s0pzidn-source/pkgs/development/cuda-modules/packages/backendStdenv.nix' does not exist

looking briefly at this. it is a path difference of 25.05 vs 25.11. 25.11 final release date is 30th Nov. and 25.05 will be deprecated then. the issue is https://github.com/anduril/jetpack-nixos/blob/master/mk-overlay.nix#L184 which hardcodes the path and will have to be adjusted to meet the supported mainline.

https://github.com/NixOS/nixpkgs/tree/master/pkgs/development/cuda-modules/backendStdenv was added by the same person who made the change in jetpack-nixos