Issue #3456748: [5.0.x] convert file extractor plugins into attribute based plugins

Closes #3456748

src/Attribute/FileExtractorExtractor.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\file_extractor\Attribute;
+
+use Drupal\Component\Plugin\Attribute\Plugin;
+use Drupal\Core\StringTranslation\TranslatableMarkup;
+
+/**
+ * Defines a FileExtractorExtractor attribute for plugin discovery.
+ *
+ * @ingroup plugin_api
+ */
+#[\Attribute(\Attribute::TARGET_CLASS)]
+class FileExtractorExtractor extends Plugin {
+
+  /**
+   * Constructs a FileExtractorExtractor attribute.
+   *
+   * @param string $id
+   *   The plugin ID.
+   * @param \Drupal\Core\StringTranslation\TranslatableMarkup|null $label
+   *   (optional) The human-readable name of the File Extractor.
+   * @param \Drupal\Core\StringTranslation\TranslatableMarkup|null $description
+   *   (optional) A short description of the File Extractor.
+   * @param string[] $dependencies
+   *   (optional) The name of modules that are required for this plugin to be
+   *   usable.
+   * @param string[] $packageDependencies
+   *   (optional) The name of Composer packages that are required for this
+   *   plugin.
+   */
+  public function __construct(
+    public readonly string $id,
+    public readonly ?TranslatableMarkup $label = NULL,
+    public readonly ?TranslatableMarkup $description = NULL,
+    public readonly array $dependencies = [],
+    public readonly array $packageDependencies = [],
+  ) {}
+
+}