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/apps/alacritty/config/alacritty.toml

@@ -0,0 +1,25 @@
+general.import = [ "~/.config/nomarchy/current/theme/alacritty.toml" ]
+
+[env]
+TERM = "xterm-256color"
+
+[terminal]
+osc52 = "CopyPaste"
+
+[font]
+normal = { family = "JetBrainsMono Nerd Font", style = "Regular" }
+bold = { family = "JetBrainsMono Nerd Font", style = "Bold" }
+italic = { family = "JetBrainsMono Nerd Font", style = "Italic" }
+size = 9
+
+[window]
+padding.x = 14
+padding.y = 14
+decorations = "None"
+
+[keyboard]
+bindings = [
+{ key = "Insert", mods = "Shift", action = "Paste" },
+{ key = "Insert", mods = "Control", action = "Copy" },
+{ key = "Return", mods = "Shift", chars = "\u001B\r" }
+]