feat(bookstack) : add BookStackSettings API resource with provider and processor

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/State/BookStackSettingsProvider.php

@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\State;
+
+use ApiPlatform\Metadata\Operation;
+use ApiPlatform\State\ProviderInterface;
+use App\ApiResource\BookStackSettings;
+use App\Repository\BookStackConfigurationRepository;
+
+final readonly class BookStackSettingsProvider implements ProviderInterface
+{
+    public function __construct(
+        private BookStackConfigurationRepository $configRepository,
+    ) {}
+
+    public function provide(Operation $operation, array $uriVariables = [], array $context = []): BookStackSettings
+    {
+        $config = $this->configRepository->findSingleton();
+        $dto    = new BookStackSettings();
+
+        if (null !== $config) {
+            $dto->url      = $config->getUrl();
+            $dto->hasToken = $config->hasToken();
+        }
+
+        return $dto;
+    }
+}