feat(platform): add cacheable metadata support to LlmsResponseAlterEvent

app/modules/platform/src/Llms/EventSubscriber/PagerLlmsSubscriber.php

@@ -24,6 +24,8 @@ public function onAlter(LlmsResponseAlterEvent $event): void {
       return;
     }
 
+    $event->getCacheableMetadata()->addCacheContexts(['url.query_args.pagers:0']);
+
     $current = $pager->getCurrentPage();
     $total = $pager->getTotalPages();
     $last = $total - 1;

app/modules/platform/src/Llms/LlmsRenderer.php

@@ -61,6 +61,8 @@ public function renderResponse(array $main_content, Request $request, RouteMatch
     $alter_event = new LlmsResponseAlterEvent($markdown, $request, $route_match);
     $this->eventDispatcher->dispatch($alter_event);
 
+    $cacheable_metadata = $cacheable_metadata->merge($alter_event->getCacheableMetadata());
+
     $response = new CacheableResponse($alter_event->getMarkdown(), 200, [
       'Content-Type' => 'text/markdown; charset=UTF-8',
       'X-Robots-Tag' => 'noindex',

app/modules/platform/src/Llms/LlmsResponseAlterEvent.php

@@ -4,17 +4,31 @@
 
 namespace Drupal\app_platform\Llms;
 
+use Drupal\Core\Cache\CacheableDependencyInterface;
+use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Routing\RouteMatchInterface;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Contracts\EventDispatcher\Event;
 
 final class LlmsResponseAlterEvent extends Event {
 
+  private CacheableMetadata $cacheableMetadata;
+
   public function __construct(
     private string $markdown,
     public readonly Request $request,
     public readonly RouteMatchInterface $routeMatch,
-  ) {}
+  ) {
+    $this->cacheableMetadata = new CacheableMetadata();
+  }
+
+  public function addCacheableDependency(CacheableDependencyInterface $dependency): void {
+    $this->cacheableMetadata = $this->cacheableMetadata->merge(CacheableMetadata::createFromObject($dependency));
+  }
+
+  public function getCacheableMetadata(): CacheableMetadata {
+    return $this->cacheableMetadata;
+  }
 
   public function getMarkdown(): string {
     return $this->markdown;