feat: Enhance email functionality and PDF generation for Sales Orders

- Enabled SMTP debugging in PHPMailer for better error tracking.
- Added a "Test send email" link in the Inventory Detail View for quick email testing.
- Implemented automatic PDF generation and email sending upon Sales Order creation.
- Created a new action for sending Sales Order emails with attached PDFs.
- Added a new AJAX action for testing outgoing email server configurations.
- Updated outgoing server settings to use new SMTP credentials.
- Improved email templates for better user experience.
- Added test scripts for validating PDF generation and email sending.

testmail.php

@@ -0,0 +1,24 @@
+<?php
+include_once 'vtlib/Vtiger/Mailer.php';
+
+$mailer = new Vtiger_Mailer();
+$mailer->IsSMTP();
+$mailer->Host = 'mail.carixin.com'; // your SMTP host
+$mailer->Port = 587; // or 465
+$mailer->SMTPAuth = true;
+$mailer->Username = 'contact@carixin.com';
+$mailer->Password = 'carixin@2025';
+$mailer->SMTPSecure = 'tls'; // or 'ssl'
+$mailer->From = 'contact@carixin.com';
+$mailer->FromName = 'ERP Test';
+$mailer->AddAddress('souldibachir3150@gmail.com', 'Admin');
+$mailer->Subject = 'SMTP Test from Vtiger';
+$mailer->Body = 'If you see this email, SMTP works!';
+$mailer->SMTPDebug = 2;
+$mailer->Debugoutput = 'html';
+$mailer->Send();
+if ($mailer->Send()) {
+    echo "✅ Mail sent successfully!";
+} else {
+    echo "❌ Mail failed: " . $mailer->ErrorInfo;
+}