change from mono-home-manager to full flake multi-system configuration

scripts/nix-maintain.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+set -e
+
+HOST=$(hostname)
+FLAKE_PATH="${HOME}/nixConfig"
+
+echo "🔁 Rebuilding system for host: $HOST"
+sudo nixos-rebuild switch --flake "$FLAKE_PATH#$HOST"
+
+echo "🧹 Collecting garbage..."
+sudo nix-collect-garbage -d
+nix store gc
+
+echo "✅ System rebuilt and cleaned."