add service file headers

backend/src/main/java/com/petshop/backend/service/ActivityLogService.java

@@ -1,3 +1,10 @@
+/*
+ * Records and retrieves user activity logs so admins can
+ * see who did what and when.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.activity.ActivityLogResponse;

backend/src/main/java/com/petshop/backend/service/AnalyticsService.java

@@ -1,3 +1,10 @@
+/*
+ * Builds the dashboard data by pulling together sales totals,
+ * inventory levels, and top-selling products.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.analytics.DashboardResponse;

backend/src/main/java/com/petshop/backend/service/AvatarStorageService.java

@@ -1,3 +1,10 @@
+/*
+ * Stores and retrieves user profile avatar images, using
+ * either local disk or Azure Blob Storage.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.entity.User;

backend/src/main/java/com/petshop/backend/service/AzureBlobService.java

@@ -1,3 +1,10 @@
+/*
+ * Low-level wrapper around the Azure Blob Storage SDK for
+ * uploading, downloading, and deleting files.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.azure.storage.blob.BlobContainerClient;

backend/src/main/java/com/petshop/backend/service/CatalogImageStorageService.java

@@ -1,3 +1,10 @@
+/*
+ * Stores and retrieves images for pets and products, using
+ * either local disk or Azure Blob Storage.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import org.slf4j.Logger;

backend/src/main/java/com/petshop/backend/service/CategoryService.java

@@ -1,3 +1,9 @@
+/*
+ * Handles creating, updating, and deleting product categories.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.category.CategoryRequest;

backend/src/main/java/com/petshop/backend/service/ChatAttachmentStorageService.java

@@ -1,3 +1,10 @@
+/*
+ * Stores and retrieves file attachments sent in chat messages,
+ * using either local disk or Azure Blob Storage.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import org.springframework.beans.factory.annotation.Autowired;

backend/src/main/java/com/petshop/backend/service/CouponService.java

@@ -1,3 +1,10 @@
+/*
+ * Handles creating, updating, and validating discount coupons
+ * that can be applied to sales.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.common.BulkDeleteRequest;

backend/src/main/java/com/petshop/backend/service/InventoryService.java

@@ -1,3 +1,10 @@
+/*
+ * Manages inventory records that track how much of each
+ * product is available at each store location.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.common.BulkDeleteRequest;

backend/src/main/java/com/petshop/backend/service/PasswordResetService.java

@@ -1,3 +1,10 @@
+/*
+ * Handles the forgot-password flow by generating a reset token,
+ * emailing it to the user, and verifying it when they reset.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.auth.ForgotPasswordResponse;

backend/src/main/java/com/petshop/backend/service/ProductService.java

@@ -1,3 +1,10 @@
+/*
+ * Manages products in the catalog, including searching,
+ * creating, updating, and handling product images.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.common.BulkDeleteRequest;

backend/src/main/java/com/petshop/backend/service/ProductSupplierService.java

@@ -1,3 +1,10 @@
+/*
+ * Manages the links between products and their suppliers,
+ * including the cost each supplier charges for a product.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.productsupplier.BulkDeleteProductSupplierRequest;

backend/src/main/java/com/petshop/backend/service/PurchaseOrderService.java

@@ -1,3 +1,10 @@
+/*
+ * Provides read-only access to purchase orders, which track
+ * orders placed with suppliers for restocking stores.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.purchaseorder.PurchaseOrderResponse;

backend/src/main/java/com/petshop/backend/service/RefundService.java

@@ -1,3 +1,10 @@
+/*
+ * Processes refunds for sales, calculating the refund amount
+ * and updating the original sale record.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.refund.RefundItemResponse;

backend/src/main/java/com/petshop/backend/service/ServiceService.java

@@ -1,3 +1,10 @@
+/*
+ * Manages pet services like grooming and veterinary care,
+ * including searching and filtering by species.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.common.BulkDeleteRequest;

backend/src/main/java/com/petshop/backend/service/StoreService.java

@@ -1,3 +1,9 @@
+/*
+ * Handles creating, updating, and deleting store locations.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.common.BulkDeleteRequest;

backend/src/main/java/com/petshop/backend/service/SupplierService.java

@@ -1,3 +1,9 @@
+/*
+ * Handles creating, updating, and deleting suppliers.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.common.BulkDeleteRequest;

backend/src/main/java/com/petshop/backend/service/UserService.java

@@ -1,3 +1,10 @@
+/*
+ * Handles creating, updating, and deleting user accounts
+ * and managing their roles and store assignments.
+ *
+ * Author: Harkamal
+ * Date: April 2026
+ */
 package com.petshop.backend.service;
 
 import com.petshop.backend.dto.common.BulkDeleteRequest;