fix: populate sidebar context for pages using Page with Sidebar template, use block_template_part for footer (v1.0.6)

- ContextBuilder now calls getSidebarData() when page template slug is
  'page-sidebar', fixing empty sidebar on pages with that template
- Added block_template_part() Twig function to TwigService for FSE
  Template Editor compatibility
- Changed footer rendering from include to block_template_part() so
  footer edits in the Template Editor take effect

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

views/base.html.twig

@@ -19,7 +19,7 @@
     </main>
 
     {% block footer %}
-        {% include 'partials/footer.html.twig' %}
+        {{ block_template_part('footer') }}
     {% endblock %}
 
     {{ wp_footer() }}