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/html-sanitizer/composer.json

@@ -0,0 +1,30 @@
+{
+    "name": "symfony/html-sanitizer",
+    "type": "library",
+    "description": "Provides an object-oriented API to sanitize untrusted HTML input for safe insertion into a document's DOM.",
+    "keywords": ["html", "sanitizer", "purifier"],
+    "homepage": "https://symfony.com",
+    "license": "MIT",
+    "authors": [
+        {
+            "name": "Titouan Galopin",
+            "email": "galopintitouan@gmail.com"
+        },
+        {
+            "name": "Symfony Community",
+            "homepage": "https://symfony.com/contributors"
+        }
+    ],
+    "require": {
+        "php": ">=8.4.1",
+        "ext-dom": "*",
+        "league/uri": "^6.5|^7.0"
+    },
+    "autoload": {
+        "psr-4": { "Symfony\\Component\\HtmlSanitizer\\": "" },
+        "exclude-from-classmap": [
+            "/Tests/"
+        ]
+    },
+    "minimum-stability": "dev"
+}