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/tty.nix

@@ -0,0 +1,29 @@
+{ pkgs, ... }:
+{
+  services.getty.greetingLine = ''\l'';
+
+  console = {
+    earlySetup = true;
+
+    # Joker palette
+    colors = [
+      "1b161f"
+      "ff5555"
+      "54c6b5"
+      "d5aa2a"
+      "bd93f9"
+      "ff79c6"
+      "8be9fd"
+      "bfbfbf"
+
+      "1b161f"
+      "ff6e67"
+      "5af78e"
+      "ffce50"
+      "caa9fa"
+      "ff92d0"
+      "9aedfe"
+      "e6e6e6"
+    ];
+  };
+}