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/lodash/_stackClear.js

@@ -0,0 +1,15 @@
+var ListCache = require('./_ListCache');
+
+/**
+ * Removes all key-value entries from the stack.
+ *
+ * @private
+ * @name clear
+ * @memberOf Stack
+ */
+function stackClear() {
+  this.__data__ = new ListCache;
+  this.size = 0;
+}
+
+module.exports = stackClear;