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/system/applications.nix

@@ -0,0 +1,30 @@
+{ config, pkgs, ... }: {
+  # System applications and utilities
+  environment.systemPackages = with pkgs; [
+    # Terminal applications
+    kitty
+    terminator
+    rio
+    greetd.tuigreet
+
+    # System monitoring
+    glances
+    inxi
+    htop
+    bottom
+    systemctl-tui
+
+    # File and data tools
+    wget
+    curl
+    mc
+
+    # Desktop integration
+    dbus
+    wayland
+    xdg-utils
+  ];
+
+  # Flatpak support
+  services.flatpak.enable = true;
+}