Website restoration: Node.js backend, restored design, GitHub sync disabled

- Replaced broken .NET backend with Node.js/Express
- Restored original website design with purple gradient hero
- Updated homepage and shop pages with Bootstrap 5 responsive design
- Disabled GitHub remote sync - all code now stored locally only
- Created backup scripts and documentation
- All changes saved on Ubuntu server at /var/www/SkyArtShop

backend/node_modules/async/unmemoize.js

@@ -0,0 +1,25 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = unmemoize;
+/**
+ * Undoes a [memoize]{@link module:Utils.memoize}d function, reverting it to the original,
+ * unmemoized form. Handy for testing.
+ *
+ * @name unmemoize
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @see [async.memoize]{@link module:Utils.memoize}
+ * @category Util
+ * @param {AsyncFunction} fn - the memoized function
+ * @returns {AsyncFunction} a function that calls the original unmemoized function
+ */
+function unmemoize(fn) {
+    return (...args) => {
+        return (fn.unmemoized || fn)(...args);
+    };
+}
+module.exports = exports.default;