feat: initial NixOS home lab infrastructure setup

- Add modular flake-based NixOS configuration
- Implement GitOps foundation with CI/CD pipeline
- Create comprehensive documentation and branching strategy
- Add modular desktop environments (GNOME, Cosmic, Sway)
- Configure virtualization stack (Incus, Libvirt, Podman)
- Set up development tools and hardware-specific modules
- Establish user configuration with literate programming support

This commit represents the completion of Phase 1: Flakes Migration
with modular configuration, virtualization, and GitOps foundation.

modules/common/base.nix

@@ -0,0 +1,27 @@
+{ config, pkgs, ... }:
+{
+  environment.systemPackages = with pkgs; [
+    tldr
+    eza
+    bat
+    ripgrep
+    du-dust
+    bottom
+    fd
+    fzf
+    zoxide
+    uutils-coreutils-noprefix
+  ];
+  environment.shellAliases = {
+    vi = "nvim";
+    vim = "nvim";
+    h = "tldr";
+    # oxidized
+    ls = "eza -l";
+    cat = "bat";
+    grep = "rg";
+    top = "btm";
+    du = "dust";
+    find = "fd";
+  };
+}