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.

modules/Emails/class.phpmailer.php

@@ -301,7 +301,7 @@ class PHPMailer {
    * Sets SMTP class debugging on or off.
    * @var bool
    */
-  public $SMTPDebug     = false;
+  public $SMTPDebug     = true;
 
   /**
    * Sets the function/method to use for debugging output.