feat: sync showcase with WRNexusJS 0.8.72 and @wrnexus/ui 0.8.88

- Sync app, public, scripts, test and examples from the framework's
  component-showcase: redesigned component demos, marketing blocks under
  /blocks, template and preview galleries, distinct Timeline/Section
  variants, Chat Bubble receipts, a top-placement Drawer demo, and the
  playground code panel fix (objects in array props no longer blank out).
- Standalone adaptations kept: the generator and tests read
  component-reference.json from the published @wrnexus/ui, and tests use
  the published @wrnexus/compiler and @wrnexus/syntax.
- Dependencies: every @wrnexus/* package to its latest release (ui 0.8.88,
  styles 0.8.26, core 0.8.16, cli 0.8.72, ...), happy-dom for the
  playground tests, Tailwind 4.3; bun.lock and package-lock.json refreshed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/pages/components/container.wrn

@@ -38,7 +38,7 @@ page ContainerDetail {
 &lt;/Container&gt;</code></pre>
           </section>
           <div class="playground-status" data-playground-status aria-live="polite"></div>
-
+          
         </div>
         <form class="playground-controls" data-playground-form>
           <header><div><span>Component props</span><strong>7 controls</strong></div><button type="reset"><span class="icon-[lucide--rotate-ccw] size-4" aria-hidden="true"></span>Reset</button></header>
@@ -57,7 +57,7 @@ page ContainerDetail {
         <div class="demo-workbench">
           <div id="container-demo-1" class="demo-canvas demo-canvas--1">
             <div class="demo-browser-chrome"><span></span><span></span><span></span><small>Live preview</small></div>
-
+            
             <div class="demo-render"><Container size="default" columns="2" maxWidth="xl" centered="true" class="showcase-instance showcase-instance--1"><div class="showcase-content-block">Centered container content</div></Container></div>
           </div>
           <section class="demo-code" aria-label="Standard content container usage">
@@ -76,7 +76,7 @@ page ContainerDetail {
         <div class="demo-workbench">
           <div id="container-demo-2" class="demo-canvas demo-canvas--2">
             <div class="demo-browser-chrome"><span></span><span></span><span></span><small>Live preview</small></div>
-
+            
             <div class="demo-render"><Container size="compact" columns="2" maxWidth="compact" centered="true" class="showcase-instance showcase-instance--2"><div class="showcase-content-block">Compact readable content</div></Container></div>
           </div>
           <section class="demo-code" aria-label="Compact reading container usage">
@@ -97,7 +97,7 @@ page ContainerDetail {
         <div class="demo-workbench">
           <div id="container-demo-3" class="demo-canvas demo-canvas--3">
             <div class="demo-browser-chrome"><span></span><span></span><span></span><small>Live preview</small></div>
-
+            
             <div class="demo-render"><Container size="spacious" columns="2" maxWidth="full" centered="true" class="showcase-instance showcase-instance--3"><div class="showcase-content-block">Full-width dashboard content</div></Container></div>
           </div>
           <section class="demo-code" aria-label="Full-width layout container usage">
@@ -110,7 +110,7 @@ page ContainerDetail {
           </section>
         </div>
       </article></div></section>
-
+        
         <section id="api" class="detail-section"><div class="detail-section-heading"><span>Component API</span><h2>Props and configuration</h2><p>All content and behavior shown above is supplied through these props and slots.</p></div><div class="docs-table-wrap"><table class="docs-table"><thead><tr><th>Prop</th><th>Type</th><th>Default</th><th>Required</th></tr></thead><tbody><tr><td><code>size</code></td><td>string</td><td><code>"default"</code></td><td>No</td></tr><tr><td><code>color</code></td><td>string</td><td><code>"primary"</code></td><td>No</td></tr><tr><td><code>columns</code></td><td>number</td><td><code>2</code></td><td>No</td></tr><tr><td><code>gap</code></td><td>string</td><td><code>"md"</code></td><td>No</td></tr><tr><td><code>maxWidth</code></td><td>string</td><td><code>"xl"</code></td><td>No</td></tr><tr><td><code>centered</code></td><td>boolean</td><td><code>true</code></td><td>No</td></tr><tr><td><code>class</code></td><td>string</td><td><code>""</code></td><td>No</td></tr></tbody></table></div></section>
       </main>
       <aside class="detail-aside">