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>

patterns/nav-offcanvas.php

@@ -0,0 +1,31 @@
+<?php
+/**
+ * Title: Navigation - Offcanvas
+ * Slug: wp-bootstrap/nav-offcanvas
+ * Categories: wp-bootstrap-navigation, header
+ * Block Types: core/template-part/header
+ * Description: Header with offcanvas mobile navigation using Bootstrap offcanvas component.
+ *
+ * @package WPBootstrap
+ * @since 0.2.0
+ */
+?>
+<!-- wp:group {"align":"full","layout":{"type":"default"}} -->
+<div class="wp-block-group alignfull">
+	<!-- wp:group {"layout":{"type":"constrained"}} -->
+	<div class="wp-block-group">
+		<!-- wp:group {"align":"wide","style":{"spacing":{"padding":{"top":"var:preset|spacing|30","bottom":"var:preset|spacing|30"}}},"layout":{"type":"flex","flexWrap":"nowrap","justifyContent":"space-between"}} -->
+		<div class="wp-block-group alignwide" style="padding-top:var(--wp--preset--spacing--30);padding-bottom:var(--wp--preset--spacing--30)">
+			<!-- wp:site-title {"level":0} /-->
+			<!-- wp:group {"style":{"spacing":{"blockGap":"var:preset|spacing|20"}},"layout":{"type":"flex","flexWrap":"nowrap","justifyContent":"right","verticalAlignment":"center"}} -->
+			<div class="wp-block-group">
+				<!-- wp:navigation {"overlayMenu":"always","overlayBackgroundColor":"base","overlayTextColor":"contrast","layout":{"type":"flex","justifyContent":"right","flexWrap":"wrap"}} /-->
+				<!-- wp:pattern {"slug":"wp-bootstrap/dark-mode-toggle"} /-->
+			</div>
+			<!-- /wp:group -->
+		</div>
+		<!-- /wp:group -->
+	</div>
+	<!-- /wp:group -->
+</div>
+<!-- /wp:group -->