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/symfony/config/Definition/Configuration.php

@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Config\Definition;
+
+use Symfony\Component\Config\Definition\Builder\TreeBuilder;
+use Symfony\Component\Config\Definition\Configurator\DefinitionConfigurator;
+use Symfony\Component\Config\Definition\Loader\DefinitionFileLoader;
+use Symfony\Component\Config\FileLocator;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+
+/**
+ * @author Yonel Ceruto <yonelceruto@gmail.com>
+ *
+ * @final
+ */
+class Configuration implements ConfigurationInterface
+{
+    public function __construct(
+        private ConfigurableInterface $subject,
+        private ?ContainerBuilder $container,
+        private string $alias,
+    ) {
+    }
+
+    public function getConfigTreeBuilder(): TreeBuilder
+    {
+        $treeBuilder = new TreeBuilder($this->alias);
+        $file = (new \ReflectionObject($this->subject))->getFileName();
+        $loader = new DefinitionFileLoader($treeBuilder, new FileLocator(\dirname($file)), $this->container);
+        $configurator = new DefinitionConfigurator($treeBuilder, $loader, $file, $file);
+
+        $this->subject->configure($configurator);
+
+        return $treeBuilder;
+    }
+}