refactor: add NixOS configuration files for server and workstation setups

config/nixos/packages/common/default.nix

@@ -0,0 +1,12 @@
+{ pkgs, ... }:
+{
+  imports = [ ./virtualisation.nix ];
+
+  environment.systemPackages = with pkgs; [
+    yubikey-manager
+    trash-cli
+    sqlite # Used for managing SQLite databases (Brave Settings etc.)
+    xcp # Rust implementation of cp/mv command
+    pandoc # Document converter (Markdown, HTML, PDF etc.) (Mostly used for static site generators)
+  ];
+}