Website is completed working, moved into billing module

modules/billing/includes/cart_helper.php

@@ -0,0 +1,22 @@
+<?php
+// Helper to read cart items stored in session and return count
+// Non-invasive: reads $_SESSION['cart'] if present and returns total quantity or items count
+
+if (session_status() === PHP_SESSION_NONE) {
+    @session_start();
+}
+
+function get_cart_count() {
+    if (!isset($_SESSION['cart']) || !is_array($_SESSION['cart'])) {
+        return 0;
+    }
+    $count = 0;
+    foreach ($_SESSION['cart'] as $item) {
+        if (is_array($item) && isset($item['quantity'])) {
+            $count += (int) $item['quantity'];
+        } else {
+            $count += 1;
+        }
+    }
+    return $count;
+}