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/webmozart/assert/.php-cs-fixer.php

@@ -0,0 +1,27 @@
+<?php
+
+$finder = PhpCsFixer\Finder::create()
+    ->in(__DIR__.'/src')
+    ->in(__DIR__.'/tests')
+;
+
+return (new PhpCsFixer\Config())
+    ->setRiskyAllowed(true)
+    ->setRules([
+        '@PSR2' => true,
+        '@Symfony' => true,
+        'ordered_imports' => true,
+        'array_syntax' => ['syntax' => 'long'],
+        'fully_qualified_strict_types' => false,
+        'global_namespace_import' => true,
+        'no_superfluous_phpdoc_tags' => false,
+        'phpdoc_annotation_without_dot' => false,
+        'phpdoc_types_order' => false,
+        'phpdoc_separation' => ['skip_unlisted_annotations' => true],
+        'phpdoc_summary' => false,
+        'phpdoc_to_comment' => false,
+        'phpdoc_align' => false,
+        'yoda_style' => false,
+    ])
+    ->setFinder($finder)
+;