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/Resource/ComposerResource.php

@@ -0,0 +1,64 @@
+<?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\Resource;
+
+/**
+ * ComposerResource tracks the PHP version and Composer dependencies.
+ *
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @final
+ */
+class ComposerResource implements SelfCheckingResourceInterface
+{
+    private array $vendors;
+
+    private static array $runtimeVendors;
+
+    public function __construct()
+    {
+        self::refresh();
+        $this->vendors = self::$runtimeVendors;
+    }
+
+    public function getVendors(): array
+    {
+        return array_keys($this->vendors);
+    }
+
+    public function __toString(): string
+    {
+        return __CLASS__;
+    }
+
+    public function isFresh(int $timestamp): bool
+    {
+        self::refresh();
+
+        return array_values(self::$runtimeVendors) === array_values($this->vendors);
+    }
+
+    private static function refresh(): void
+    {
+        self::$runtimeVendors = [];
+
+        foreach (get_declared_classes() as $class) {
+            if ('C' === $class[0] && str_starts_with($class, 'ComposerAutoloaderInit')) {
+                $r = new \ReflectionClass($class);
+                $v = \dirname($r->getFileName(), 2);
+                if (is_file($v.'/composer/installed.json')) {
+                    self::$runtimeVendors[$v] = @filemtime($v.'/composer/installed.json');
+                }
+            }
+        }
+    }
+}