refactor: implement component-based architecture for enhanced maintainability

- Reorganize directory structure into core/, features/, and themes/
- Colocate application Nix logic, configs, scripts, and theme overrides
- Implement 'Inversion of Control' for theming: apps now pull theme-specific layouts
- Update flake.nix and shared library paths to match the new structure
- Document the new Feature-Centric architecture in README.md

features/scripts/utils/nomarchy-test-vm

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+# Build and run the Nomarchy VM (installed environment) for testing.
+
+echo "Building Nomarchy VM (Installed Environment)..."
+echo "Note: To test the INSTALLER, run 'nomarchy-test-installer' instead."
+nix build .#nixosConfigurations.vm.config.system.build.vm
+
+if [ $? -eq 0 ]; then
+    echo "Success! Launching VM..."
+    ./result/bin/run-nomarchy-vm
+else
+    echo "Error: VM build failed."
+    exit 1
+fi