Add logo image to newsletter HTML in index.php for enhanced branding. Adjusted layout for improved presentation.

index.php

@@ -447,6 +447,11 @@ function buildNewsletterHtml(array $config, array $articles, string $periodLabel
       <tr>
         <td align="center" style="padding:12px 8px;">
           <table role="presentation" width="690" border="0" cellspacing="0" cellpadding="0" class="email-container" style="width:100%;max-width:690px;background:#ffffff;">
+            <tr>
+              <td align="center" style="padding:8px 26px 14px 26px;">
+                <img src="https://www.thomas-krenn.com/res/pics/tk_logo_340px.png" width="170" alt="Thomas-Krenn Logo" style="display:block;margin:0 auto;border:0;outline:none;text-decoration:none;height:auto;">
+              </td>
+            </tr>
             <tr>
               <td style="padding:0 26px;" class="mobile-padding">
                 <table role="presentation" width="100%" border="0" cellspacing="0" cellpadding="0" style="width:100%;background:#10233a;">