chore: update ESLint to v9 and use the new nextcloud-eslint-config

Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

Author: susnux

.eslintrc.json

@@ -0,0 +1,21 @@
+/*!
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: CC0-1.0
+ */
+
+import { recommendedLibrary } from '@nextcloud/eslint-config'
+
+export default [
+	...recommendedLibrary,
+
+	// Fix tsdoc generation
+	{
+		files: ['lib/**.ts'],
+		rules: {
+			'jsdoc/check-tag-names': [
+				'error',
+				{ definedTags: ['packageDocumentation'] },
+			],
+		},
+	},
+]