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/uri-interfaces/Contracts/FragmentDirective.php

@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * League.Uri (https://uri.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.
+ */
+
+declare(strict_types=1);
+
+namespace League\Uri\Contracts;
+
+use Stringable;
+
+/**
+ * @see https://wicg.github.io/scroll-to-text-fragment/#the-fragment-directive
+ *
+ * @method string toFragmentValue() returns the encoded string representation of the directive as a fragment string
+ */
+interface FragmentDirective extends Stringable
+{
+    /**
+     * The decoded Directive name.
+     *
+     * @return non-empty-string
+     */
+    public function name(): string;
+
+    /**
+     * The decoded Directive value.
+     */
+    public function value(): ?string;
+
+    /**
+     * The encoded string representation of the directive.
+     */
+    public function toString(): string;
+
+    /**
+     * The encoded string representation of the fragment using
+     * the Stringable interface.
+     *
+     * @see FragmentDirective::toString()
+     */
+    public function __toString(): string;
+
+    /**
+     * Tells whether the submitted value is equals to the string
+     * representation of the given directive.
+     */
+    public function equals(mixed $directive): bool;
+}