refactor: consolidate app configurations and utility scripts

- Move 32+ app-specific scripts from features/apps/scripts/ to features/scripts/utils/ for centralized packaging.
- Create individual Nix modules for orphaned app configurations (btop, kitty, tmux, etc.) in features/apps/ using xdg.configFile.
- Fix broken paths in core/system/makima.nix and features/apps/vscode.nix.
- Update VSCode configuration to use the modern 'profiles.default.userSettings' API, resolving deprecation warnings.
- Merge duplicate 'nomarchy-launch-walker' scripts into a single robust utility.
- Remove stale root 'config/' directory.
- Update README.md and docs/creating-themes.md to reflect the new architecture and keybindings.
- Ensure all modules are correctly imported and verified via nix flake check.

features/apps/vscode.nix

@@ -1,7 +1,11 @@
 { config, pkgs, lib, ... }:
 
 let
-  themeConfig = builtins.fromJSON (builtins.readFile (../../themes/palettes + "/${config.nomarchy.theme}/vscode.json"));
+  themePath = ../../themes/palettes + "/${config.nomarchy.theme}/apps/vscode.json";
+  themeConfig = if builtins.pathExists themePath then
+    builtins.fromJSON (builtins.readFile themePath)
+  else
+    { name = "Default Dark Modern"; };
 
   # Development extensions that match the system theme
   devExtensions = with pkgs.vscode-extensions; [
@@ -40,7 +44,7 @@ in
     programs.vscode = {
       enable = lib.mkDefault true;
       package = lib.mkDefault pkgs.vscode;
-      userSettings = lib.mkDefault {
+      profiles.default.userSettings = lib.mkDefault {
         "update.mode" = "none";
         "workbench.colorTheme" = themeConfig.name;
         "window.titleBarStyle" = "custom";