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/dependency-injection/Compiler/RegisterReverseContainerPass.php

@@ -0,0 +1,65 @@
+<?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\DependencyInjection\Compiler;
+
+use Symfony\Component\DependencyInjection\Argument\ServiceClosureArgument;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\DependencyInjection\Definition;
+use Symfony\Component\DependencyInjection\Reference;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ */
+class RegisterReverseContainerPass implements CompilerPassInterface
+{
+    private bool $beforeRemoving;
+
+    public function __construct(bool $beforeRemoving)
+    {
+        $this->beforeRemoving = $beforeRemoving;
+    }
+
+    /**
+     * @return void
+     */
+    public function process(ContainerBuilder $container)
+    {
+        if (!$container->hasDefinition('reverse_container')) {
+            return;
+        }
+
+        $refType = $this->beforeRemoving ? ContainerInterface::IGNORE_ON_UNINITIALIZED_REFERENCE : ContainerInterface::EXCEPTION_ON_INVALID_REFERENCE;
+        $services = [];
+        foreach ($container->findTaggedServiceIds('container.reversible') as $id => $tags) {
+            $services[$id] = new Reference($id, $refType);
+        }
+
+        if ($this->beforeRemoving) {
+            // prevent inlining of the reverse container
+            $services['reverse_container'] = new Reference('reverse_container', $refType);
+        }
+        $locator = $container->getDefinition('reverse_container')->getArgument(1);
+
+        if ($locator instanceof Reference) {
+            $locator = $container->getDefinition((string) $locator);
+        }
+        if ($locator instanceof Definition) {
+            foreach ($services as $id => $ref) {
+                $services[$id] = new ServiceClosureArgument($ref);
+            }
+            $locator->replaceArgument(0, $services);
+        } else {
+            $locator->setValues($services);
+        }
+    }
+}