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/http-client/ThrottlingHttpClient.php

@@ -0,0 +1,51 @@
+<?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\HttpClient;
+
+use Symfony\Component\RateLimiter\LimiterInterface;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
+use Symfony\Contracts\HttpClient\ResponseInterface;
+use Symfony\Contracts\Service\ResetInterface;
+
+/**
+ * Limits the number of requests within a certain period.
+ */
+class ThrottlingHttpClient implements HttpClientInterface, ResetInterface
+{
+    use DecoratorTrait {
+        reset as private traitReset;
+    }
+
+    public function __construct(
+        HttpClientInterface $client,
+        private readonly LimiterInterface $rateLimiter,
+    ) {
+        $this->client = $client;
+    }
+
+    public function request(string $method, string $url, array $options = []): ResponseInterface
+    {
+        $response = $this->client->request($method, $url, $options);
+
+        if (0 < $waitDuration = $this->rateLimiter->reserve()->getWaitDuration()) {
+            $response->getInfo('pause_handler')($waitDuration);
+        }
+
+        return $response;
+    }
+
+    public function reset(): void
+    {
+        $this->traitReset();
+        $this->rateLimiter->reset();
+    }
+}