Prevent library duplicates logic from blocking UI

src/modules/library/workers/LibraryDuplicatesWorker.ts

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) Contributors to the Suwayomi project
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+import {
+    findDuplicatesByTitle,
+    findDuplicatesByTitleAndAlternativeTitles,
+} from '@/modules/library/util/LibraryDuplicates.util.ts';
+import { LibraryDuplicatesWorkerInput } from '@/modules/library/Library.types.ts';
+
+// eslint-disable-next-line no-restricted-globals
+self.onmessage = async (event: MessageEvent<LibraryDuplicatesWorkerInput>) => {
+    const { mangas } = event.data;
+    const { checkAlternativeTitles } = event.data;
+
+    if (checkAlternativeTitles) {
+        postMessage(findDuplicatesByTitleAndAlternativeTitles(mangas));
+        return;
+    }
+
+    postMessage(findDuplicatesByTitle(mangas));
+};