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

themes/palettes/catppuccin-latte/apps/neovim.lua

@@ -0,0 +1,16 @@
+return {
+	{
+		"catppuccin/nvim",
+		name = "catppuccin",
+		priority = 1000,
+		opts = {
+			flavour = "latte",
+		},
+	},
+	{
+		"LazyVim/LazyVim",
+		opts = {
+			colorscheme = "catppuccin-latte",
+		},
+	},
+}