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/Compiler/RemoveAbstractDefinitionsPass.php

@@ -0,0 +1,36 @@
+<?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\Compiler;
+
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+
+/**
+ * Removes abstract Definitions.
+ */
+class RemoveAbstractDefinitionsPass implements CompilerPassInterface
+{
+    /**
+     * Removes abstract definitions from the ContainerBuilder.
+     *
+     * @return void
+     */
+    public function process(ContainerBuilder $container)
+    {
+        foreach ($container->getDefinitions() as $id => $definition) {
+            if ($definition->isAbstract()) {
+                $container->resolveEnvPlaceholders($definition);
+                $container->removeDefinition($id);
+                $container->log($this, \sprintf('Removed service "%s"; reason: abstract.', $id));
+            }
+        }
+    }
+}