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/Attribute/AutowireCallable.php

@@ -0,0 +1,50 @@
+<?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\Attribute;
+
+use Symfony\Component\DependencyInjection\Definition;
+use Symfony\Component\DependencyInjection\Exception\LogicException;
+use Symfony\Component\DependencyInjection\Reference;
+
+/**
+ * Attribute to tell which callable to give to an argument of type Closure.
+ */
+#[\Attribute(\Attribute::TARGET_PARAMETER)]
+class AutowireCallable extends Autowire
+{
+    /**
+     * @param bool|class-string $lazy Whether to use lazy-loading for this argument
+     */
+    public function __construct(
+        string|array|null $callable = null,
+        ?string $service = null,
+        ?string $method = null,
+        bool|string $lazy = false,
+    ) {
+        if (!(null !== $callable xor null !== $service)) {
+            throw new LogicException('#[AutowireCallable] attribute must declare exactly one of $callable or $service.');
+        }
+        if (null === $service && null !== $method) {
+            throw new LogicException('#[AutowireCallable] attribute cannot have a $method without a $service.');
+        }
+
+        parent::__construct($callable ?? [new Reference($service), $method ?? '__invoke'], lazy: $lazy);
+    }
+
+    public function buildDefinition(mixed $value, ?string $type, \ReflectionParameter $parameter): Definition
+    {
+        return (new Definition($type = \is_array($this->lazy) ? current($this->lazy) : ($type ?: 'Closure')))
+            ->setFactory(['Closure', 'fromCallable'])
+            ->setArguments([\is_array($value) ? $value + [1 => '__invoke'] : $value])
+            ->setLazy($this->lazy || 'Closure' !== $type && 'callable' !== (string) $parameter->getType());
+    }
+}