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/league/csv/src/Serializer/ArrayShape.php

@@ -0,0 +1,32 @@
+<?php
+
+/**
+ * League.Csv (https://csv.thephpleague.com)
+ *
+ * (c) Ignace Nyamagana Butera <nyamsprod@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace League\Csv\Serializer;
+
+use function in_array;
+
+enum ArrayShape: string
+{
+    case List = 'list';
+    case Csv = 'csv';
+    case Json = 'json';
+
+    public function equals(mixed $value): bool
+    {
+        return $value instanceof self
+            && $value === $this;
+    }
+
+    public function isOneOf(self ...$types): bool
+    {
+        return in_array($this, $types, true);
+    }
+}