Remove unused configurations and packages from laptop setup

- Removed USBGuard configuration and its associated comments from configuration.nix.
- Cleaned up flake.nix by removing unnecessary overlays.
- Updated home.nix to remove references to Helium and Proton, and added Steam.
- Deleted secrets.default.nix and secrets.secrets.yaml files for security reasons.
- Removed Omen laptop specific configuration from omen.nix.
- Deleted vencord.nix as it is no longer needed.

nixos/omen.nix

@@ -1,64 +0,0 @@
-# Omen laptop configuration for NixOS
-# Import this only if you have an HP Omen laptop
-{
-  config,
-  pkgs,
-  ...
-}: let
-  hp-omen-linux-module = pkgs.callPackage (
-    {
-      kernel ? config.boot.kernelPackages.kernel,
-      stdenv,
-      fetchFromGitHub,
-    }:
-      stdenv.mkDerivation (finalAttrs: {
-        pname = "hp-omen-linux-module";
-        version = "rebase-6.14";
-        src = fetchFromGitHub {
-          owner = "ranisalt";
-          repo = "hp-omen-linux-module";
-          rev = finalAttrs.version;
-          sha256 = "sha256-2zCm29bdboSjRm/caMjBPGNc0tZXPUnIIYlHxxfhAok=";
-        };
-        setSourceRoot = ''
-          export sourceRoot=$(pwd)/${finalAttrs.src.name}/src
-        '';
-        nativeBuildInputs = kernel.moduleBuildDependencies;
-        makeFlags = [
-          "KERNELDIR=${kernel.dev}/lib/modules/${kernel.modDirVersion}/build"
-        ];
-        installPhase = ''
-          runHook preInstall
-          install hp-wmi.ko -Dm444 -t $out/lib/modules/${kernel.modDirVersion}/kernel/drivers/platform/x86/hp/
-          runHook postInstall
-        '';
-      })
-  ) {kernel = config.boot.kernelPackages.kernel;};
-in {
-  boot.extraModulePackages = [hp-omen-linux-module];
-  boot.kernelModules = ["hp-wmi"];
-  boot.kernelParams = ["hp_wmi.force_slow_fan_control=1"];
-
-  users.groups.omen-rgb = {};
-  users.users.${config.var.username}.extraGroups = ["omen-rgb"];
-
-  systemd.tmpfiles.rules = [
-    "w /sys/devices/platform/hp-wmi/rgb_zones/zone00 0660 root omen-rgb -"
-    "w /sys/devices/platform/hp-wmi/rgb_zones/zone01 0660 root omen-rgb -"
-    "w /sys/devices/platform/hp-wmi/rgb_zones/zone02 0660 root omen-rgb -"
-    "w /sys/devices/platform/hp-wmi/rgb_zones/zone03 0660 root omen-rgb -"
-  ];
-
-  services.udev.extraRules = ''
-    SUBSYSTEM=="platform", KERNEL=="hp-wmi", ACTION=="add", \
-    RUN+="${pkgs.coreutils-full}/bin/sleep 2", \
-    RUN+="${pkgs.coreutils}/bin/chgrp omen-rgb /sys/devices/platform/hp-wmi/rgb_zones/zone00", \
-    RUN+="${pkgs.coreutils}/bin/chmod 0660 /sys/devices/platform/hp-wmi/rgb_zones/zone00", \
-    RUN+="${pkgs.coreutils}/bin/chgrp omen-rgb /sys/devices/platform/hp-wmi/rgb_zones/zone01", \
-    RUN+="${pkgs.coreutils}/bin/chmod 0660 /sys/devices/platform/hp-wmi/rgb_zones/zone01", \
-    RUN+="${pkgs.coreutils}/bin/chgrp omen-rgb /sys/devices/platform/hp-wmi/rgb_zones/zone02", \
-    RUN+="${pkgs.coreutils}/bin/chmod 0660 /sys/devices/platform/hp-wmi/rgb_zones/zone02", \
-    RUN+="${pkgs.coreutils}/bin/chgrp omen-rgb /sys/devices/platform/hp-wmi/rgb_zones/zone03", \
-    RUN+="${pkgs.coreutils}/bin/chmod 0660 /sys/devices/platform/hp-wmi/rgb_zones/zone03"
-  '';
-}

nixos/vencord.nix

@@ -1,5 +0,0 @@
-{ pkgs, ... }: {
-  environment.systemPackages = with pkgs; [
-    vencord
-  ];
-}