Add superuser new customer email notification preferences

services/nginx/app/classes/email.php

@@ -511,4 +511,47 @@ use Psr\Http\Client\ClientExceptionInterface;
             $this->attachments
         );
     }
+
+    /**
+     * @throws Exception
+     */
+    public function sendNewCustomerRegistrationNotifications(int $customer_number): void
+    {
+        $customer = (new users_o())->getUserByCustomerNumber($customer_number);
+        if (!$customer->exists()) {
+            throw new Exception('Customer not found with customer number: ' . $customer_number);
+        }
+
+        $customerName = $customer->getCustomerName((int)$customer->customer_number->value()) ?: 'Unknown customer';
+        $safeCustomerName = htmlspecialchars($customerName, ENT_QUOTES, 'UTF-8');
+        $safeCustomerNumber = (int)$customer->customer_number->value();
+        $customerUrl = 'https://truckwash.io/superuser/users?search=' . $safeCustomerNumber;
+        $message = "
+            <p>A new customer has registered on truckwash.io.</p>
+            <p>
+                <strong>Customer number:</strong> $safeCustomerNumber<br>
+                <strong>Customer name:</strong> $safeCustomerName
+            </p>
+            <p><a href='$customerUrl'>Open customer in Superuser</a></p>
+        ";
+
+        foreach ((new users_o())->getSuperuserNewCustomerEmailNotificationRecipients() as $recipient) {
+            $recipientEmail = trim((string)($recipient['email'] ?? ''));
+            if ($recipientEmail === '') {
+                continue;
+            }
+
+            $recipientName = trim((string)($recipient['display_name'] ?? ''));
+            if ($recipientName === '') {
+                $recipientName = $recipientEmail;
+            }
+
+            $this->sendEmail(
+                $recipientEmail,
+                $recipientName,
+                'New customer registered on Truck Wash',
+                $message,
+            );
+        }
+    }
 }