v0.2.0 - Design Editor: templates, patterns, header/footer variations

Full Design Editor compatibility with custom block categories, page templates,
header/footer variations, and navigation styles. Both FSE (admin) and Twig
(frontend) sides kept in sync.

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

views/pages/full-width.html.twig

@@ -0,0 +1,18 @@
+{% extends 'base.html.twig' %}
+
+{% block content %}
+<div class="container-fluid px-0">
+    <article>
+        {% if post.thumbnail %}
+            <img src="{{ post.thumbnail }}" class="w-100 mb-4" alt="{{ post.title|e('html_attr') }}">
+        {% endif %}
+        <div class="container">
+            <h1 class="mb-4">{{ post.title }}</h1>
+
+            <div class="post-content">
+                {{ post.content|raw }}
+            </div>
+        </div>
+    </article>
+</div>
+{% endblock %}