switch to programs.steam and proton-ge-bin from nixpkgs

proton-ge from nix-gaming is deprecated now that proton-ge-bin is in
nixpkgs

home/programs/games/steam.nix

@@ -1,32 +0,0 @@
-{
-  pkgs,
-  inputs,
-  ...
-}: let
-  steam-with-pkgs = pkgs.steam.override {
-    extraPkgs = pkgs:
-      with pkgs; [
-        xorg.libXcursor
-        xorg.libXi
-        xorg.libXinerama
-        xorg.libXScrnSaver
-        libpng
-        libpulseaudio
-        libvorbis
-        stdenv.cc.cc.lib
-        libkrb5
-        keyutils
-        gamescope
-        gamemode
-        mangohud
-      ];
-    extraProfile = "export STEAM_EXTRA_COMPAT_TOOLS_PATHS='${inputs.nix-gaming.packages.${pkgs.system}.proton-ge}'";
-  };
-in {
-  home.packages = with pkgs; [
-    steam-with-pkgs
-    steam-run
-    steamtinkerlaunch
-    protontricks
-  ];
-}