feat: Implement invoice generation and emailing functionality

- Added invoice generation logic using DomPDF.
- Integrated invoice data retrieval from the API.
- Implemented language determination for invoices based on customer data.
- Added options to email invoices to customers and admin.
- Included HTML output option for direct viewing in the browser.
- Ensured proper redirection and error handling throughout the process.

api/v2/post/history.php

@@ -1,5 +1,6 @@
 <?php
 defined($security_key) or exit;
+
 //------------------------------------------
 // History
 //------------------------------------------
@@ -209,9 +210,8 @@ if (isset($post_content['sn']) && isset($post_content['payload'])){
         if ($equipmentUpdate == 1){
             //get HW + SW from PortalAPI
             if ($post_content['type'] == 'firmware'){
-                    $test = json_decode($post_content['payload']);
-                    $hw_version = 	$test->HW;
-                    $sw_version = 	$test->HEX_FW;
+                    $hw_version = 	$post_content['payload']['HW'];
+                    $sw_version = 	$post_content['payload']['HEX_FW'];
                 }
                 else {
                     //GET HW + SW from object