Update default backend API URL in index.html for improved functionality

- Changed the default backend API URL from 'https://hexaflock-worker.mrarwyn.workers.dev' to 'https://www.hexaflock.com' in the input field and script.
- This update ensures consistency in API usage across the application.

Author: arwyn6969

static_site/index.html

@@ -127,7 +127,7 @@
         <div class="card">
           <div class="panel-label">Stamp (Optional Backend)</div>
           <div class="row inputs">
-            <input id="api" type="text" placeholder="Backend API URL (e.g., https://your-backend.example.com)" value="https://hexaflock-worker.mrarwyn.workers.dev" />
+            <input id="api" type="text" placeholder="Backend API URL (e.g., https://your-backend.example.com)" value="https://www.hexaflock.com" />
             <button class="btn" onclick="saveApi()">Save</button>
           </div>
           <div class="row inputs">
@@ -161,7 +161,7 @@
 
     <script>
       // Default backend API (workers.dev)
-      const DEFAULT_API = 'https://hexaflock-worker.mrarwyn.workers.dev';
+      const DEFAULT_API = 'https://www.hexaflock.com';
       // Palette and masks (inline, minimal dependencies)
       const PALETTE = [
         '#000000','#FFFFFF','#F0F0F0','#D3D3D3','#FF8C00','#FFA500','#FF4500','#DC143C','#FF0000','#32CD32','#00FF00','#6B4E3D','#808080'