feat: add fflate library for file decompression and implement file download functionality in BookOfflineButton component

src/lib/services/book.service.ts

@@ -115,6 +115,27 @@ export class BookService extends BaseApiService {
     }
   }
 
+  static async getFile(bookId: string): Promise<Response> {
+    try {
+      const config = await this.getKomgaConfig();
+      const url = this.buildUrl(config, `books/${bookId}/file`);
+      const headers = this.getAuthHeaders(config);
+
+      const response = await fetch(url, {
+        method: "GET",
+        headers,
+      });
+
+      if (!response.ok) {
+        throw new AppError(ERROR_CODES.BOOK.NOT_FOUND);
+      }
+
+      return response;
+    } catch (error) {
+      throw new AppError(ERROR_CODES.BOOK.NOT_FOUND, {}, error);
+    }
+  }
+
   static async getCover(bookId: string): Promise<Response> {
     try {
       // Récupérer les préférences de l'utilisateur