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-toggle-notification-silencing

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+makoctl mode -t do-not-disturb
+
+if makoctl mode | grep -q 'do-not-disturb'; then
+  notify-send -u low "󰂛    Silenced notifications"
+else
+  notify-send -u low "󰂚    Enabled notifications"
+fi
+
+pkill -RTMIN+10 waybar