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/signal-exit/LICENSE.txt

@@ -0,0 +1,16 @@
+The ISC License
+
+Copyright (c) 2015, Contributors
+
+Permission to use, copy, modify, and/or distribute this software
+for any purpose with or without fee is hereby granted, provided
+that the above copyright notice and this permission notice
+appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
+OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE
+LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES
+OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.