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/contracts/Service/Attribute/SubscribedService.php

@@ -0,0 +1,47 @@
+<?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\Contracts\Service\Attribute;
+
+use Symfony\Contracts\Service\ServiceMethodsSubscriberTrait;
+use Symfony\Contracts\Service\ServiceSubscriberInterface;
+
+/**
+ * For use as the return value for {@see ServiceSubscriberInterface}.
+ *
+ * @example new SubscribedService('http_client', HttpClientInterface::class, false, new Target('githubApi'))
+ *
+ * Use with {@see ServiceMethodsSubscriberTrait} to mark a method's return type
+ * as a subscribed service.
+ *
+ * @author Kevin Bond <kevinbond@gmail.com>
+ */
+#[\Attribute(\Attribute::TARGET_METHOD | \Attribute::TARGET_PROPERTY)]
+final class SubscribedService
+{
+    /** @var object[] */
+    public array $attributes;
+
+    /**
+     * @param string|null     $key        The key to use for the service
+     * @param string|null     $type       The service type (a class name, "string", "iterable", etc.)
+     * @param bool            $nullable   Whether the service is optional
+     * @param object|object[] $attributes One or more dependency injection attributes to use
+     */
+    public function __construct(
+        public ?string $key = null,
+        public ?string $type = null,
+        public bool $nullable = false,
+        array|object $attributes = [],
+    ) {
+        $this->attributes = \is_array($attributes) ? $attributes : [$attributes];
+    }
+}