fix(website): keep omitted language selectors free of whitespace

Indent the optional language selector with its value so a nonindexable draft does not generate a line containing only spaces. Indexed-page markup is unchanged.

Validation: website.py check passes all 12 maintenance regressions; synchronization changes only the draft header blank line.

website/public/blog/reverse-engineering-models/index.html

@@ -79,7 +79,7 @@
           <a href="../../faq/">FAQ</a>
         </nav>
         <div class="header-social">
-      
+
           <button class="theme-toggle" type="button" data-theme-toggle hidden>
             <svg class="theme-moon" width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.6" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true" focusable="false">
               <path d="M20.9 13a9 9 0 0 1-9.9-9.9A9 9 0 1 0 20.9 13Z" />

website/templates/header.html.tmpl

@@ -7,7 +7,7 @@
     >
     <nav class="navigation" aria-label="Main navigation">$navigation</nav>
     <div class="header-social">
-      $language_picker
+$language_picker
       <button class="theme-toggle" type="button" data-theme-toggle hidden>
         <svg class="theme-moon" width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.6" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true" focusable="false">
           <path d="M20.9 13a9 9 0 0 1-9.9-9.9A9 9 0 1 0 20.9 13Z" />