fix(frontend): align post thumbnail display with reference

inc/helpers/posts-renderer/config.php

@@ -143,7 +143,7 @@ if (!function_exists('aksrt_renderer_excerpt_markup')) {
 
 if (!function_exists('aksrt_renderer_curated_images')) {
 	/** @return string[] */
-	function aksrt_renderer_curated_images(int $post_id, string $size, int $limit = 8): array {
+	function aksrt_renderer_curated_images(int $post_id, string $size): array {
 		$raw = class_exists('\AKSRT\Core\PostMetaBox')
 			? (string) \AKSRT\Core\PostMetaBox::get_meta_value($post_id, 'featured_slide', '')
 			: '';
@@ -154,7 +154,7 @@ if (!function_exists('aksrt_renderer_curated_images')) {
 				$images[] = $image;
 			}
 		}
-		return array_slice($images, 0, $limit);
+		return $images;
 	}
 }
 
@@ -179,7 +179,8 @@ if (!function_exists('aksrt_renderer_sized_image')) {
 				return esc_url_raw($sized);
 			}
 		}
-		return esc_url_raw($image);
+		// A missing attachment is not a relative image URL. Let the next configured source resolve it.
+		return ctype_digit($image) ? '' : esc_url_raw($image);
 	}
 }