refactor: Cleanup git state - commit all staged changes

Major refactoring cleanup:
- Add new controller architecture (class-controller-*.php)
- Add new settings-v2 UI (views/settings-v2/)
- Add new CSS architecture (agentic-sidebar.css, tokens)
- Add esbuild build pipeline (scripts/build.js, package.json)
- Add composer dependencies (vendor/)
- Add frontend src directory (assets/js/src/index.jsx)
- Add documentation files
- Remove old/obsolete files (class-settings.php, old CSS)

This commits all pending changes from previous refactoring efforts.

vendor/phpdocumentor/guides/src/NodeRenderers/Html/MenuNodeRenderer.php

@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of phpDocumentor.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ *
+ * @link https://phpdoc.org
+ */
+
+namespace phpDocumentor\Guides\NodeRenderers\Html;
+
+use phpDocumentor\Guides\NodeRenderers\NodeRenderer;
+use phpDocumentor\Guides\Nodes\Menu\ContentMenuNode;
+use phpDocumentor\Guides\Nodes\Menu\MenuNode;
+use phpDocumentor\Guides\Nodes\Menu\TocNode;
+use phpDocumentor\Guides\Nodes\Node;
+use phpDocumentor\Guides\RenderContext;
+use phpDocumentor\Guides\TemplateRenderer;
+use Webmozart\Assert\Assert;
+
+use function is_a;
+
+/** @implements NodeRenderer<MenuNode> */
+final class MenuNodeRenderer implements NodeRenderer
+{
+    public function __construct(private readonly TemplateRenderer $renderer)
+    {
+    }
+
+    public function render(Node $node, RenderContext $renderContext): string
+    {
+        Assert::isInstanceOf($node, MenuNode::class);
+
+        if ($node->getOption('hidden', false)) {
+            return '';
+        }
+
+        return $this->renderer->renderTemplate(
+            $renderContext,
+            $this->getTemplate($node),
+            ['node' => $node],
+        );
+    }
+
+    private function getTemplate(Node $node): string
+    {
+        if ($node instanceof TocNode) {
+            return 'body/menu/table-of-content.html.twig';
+        }
+
+        if ($node instanceof ContentMenuNode) {
+            return 'body/menu/content-menu.html.twig';
+        }
+
+        return 'body/menu/menu.html.twig';
+    }
+
+    public function supports(string $nodeFqcn): bool
+    {
+        return $nodeFqcn === MenuNode::class || is_a($nodeFqcn, MenuNode::class, true);
+    }
+}