refactor: major architectural restructure for theme-centric organization

Theme System:
- Move all theme app configs to apps/ subdirectory (20 themes)
- Add theme-loader.nix for dynamic theme config deployment
- Simplify stylix.nix to focus on base theming only

Override System:
- Add overrides.nix for file-based config overrides
- Add behavior-configs.nix for non-visual configuration
- Split hypr/nomarchy.conf into behavior vs visual sections

Module Improvements:
- Add lib.mkDefault to all customizable settings
- Add modules/lib/ with shared utilities and state schema
- Update all home and system modules for downstream overridability

Installer:
- New minimal TTY installer (installer/install.sh)
- Golden path: BTRFS + LUKS2 (disko-golden.nix)
- New installer-iso.nix for TTY-only installation
- Keep graphical installer as installerIsoGraphical option

Cleanup:
- Remove obsolete install.sh, disko-ext4.nix, install-nomarchy.sh
- Update live-iso.nix references
- Add .claude/ to .gitignore for local IDE settings

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

modules/home/fonts.nix

@@ -1,8 +1,8 @@
-{ ... }:
+{ lib, ... }:
 
 {
   config = {
-    fonts.fontconfig.enable = true;
-    xdg.dataFile."fonts/nomarchy.ttf".source = ../../config/nomarchy.ttf;
+    fonts.fontconfig.enable = lib.mkDefault true;
+    xdg.dataFile."fonts/nomarchy.ttf".source = lib.mkDefault ../../config/nomarchy.ttf;
   };
 }