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/parsica-php/parsica/tests/Parser/unicodeTest.php

@@ -0,0 +1,33 @@
+<?php declare(strict_types=1);
+/**
+ * This file is part of the Parsica library.
+ *
+ * Copyright (c) 2020 Mathias Verraes <mathias@verraes.net>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Tests\Parsica\Parsica\Parser;
+
+use PHPUnit\Framework\TestCase;
+use Parsica\Parsica\PHPUnit\ParserAssertions;
+use function Parsica\Parsica\char;
+
+final class unicodeTest extends TestCase
+{
+    use ParserAssertions;
+
+    /** @test */
+    public function mbstring_must_be_installed()
+    {
+        $this->assertTrue(function_exists('mb_detect_encoding'), "ext-mbstring must be installed.");
+    }
+
+    /** @test */
+    public function parses_unicode()
+    {
+        $parser = char("🥰");
+        $this->assertParses("🥰 hello", $parser, "🥰");
+    }
+}