Reorganize modules

modules/bitwarden.nix

@@ -0,0 +1,11 @@
+{ config, pkgs, ... }:
+
+{
+  nixpkgs.config.permittedInsecurePackages = [
+    "electron-39.8.10"
+  ];
+
+  environment.systemPackages = with pkgs; [
+    bitwarden-desktop
+  ];
+}