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/console/Tester/Constraint/CommandIsSuccessful.php

@@ -0,0 +1,43 @@
+<?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\Console\Tester\Constraint;
+
+use PHPUnit\Framework\Constraint\Constraint;
+use Symfony\Component\Console\Command\Command;
+
+final class CommandIsSuccessful extends Constraint
+{
+    public function toString(): string
+    {
+        return 'is successful';
+    }
+
+    protected function matches($other): bool
+    {
+        return Command::SUCCESS === $other;
+    }
+
+    protected function failureDescription($other): string
+    {
+        return 'the command '.$this->toString();
+    }
+
+    protected function additionalFailureDescription($other): string
+    {
+        $mapping = [
+            Command::FAILURE => 'Command failed.',
+            Command::INVALID => 'Command was invalid.',
+        ];
+
+        return $mapping[$other] ?? \sprintf('Command returned exit status %d.', $other);
+    }
+}