Add MarkSeen Functionality to Notification System

- Implemented the MarkSeen method in the notification client to mark notifications as seen, enhancing user interaction with notifications.
- Added MarkSeenRequest and MarkSeenResponse structs to facilitate the request and response handling for marking notifications.
- Updated the NotificationService interface to include the new MarkSeen method, ensuring consistency across the service layer.
- Enhanced the SDK with a QuickMarkSeen convenience method for easier usage in client applications.
- Included logging for successful and failed attempts to mark notifications as seen, improving traceability and debugging capabilities.

pkg/notification/entities.go

@@ -135,6 +135,8 @@ type NotificationItem struct {
 	Status      string            `json:"status"`
 	ScheduledAt int64             `json:"scheduled_at"`
 	IsScheduled bool              `json:"is_scheduled"`
+	Seen        bool              `json:"seen"`
+	SeenAt      int64             `json:"seen_at"`
 }
 
 // NotificationListResponse represents the response from getting notifications list
@@ -162,3 +164,13 @@ type GetNotificationsRequest struct {
 	Page      int    `json:"page,omitempty" valid:"optional"`
 	PerPage   int    `json:"per_page,omitempty" valid:"optional"`
 }
+
+// MarkSeenRequest represents the request for marking a notification as seen
+type MarkSeenRequest struct {
+	NotificationID string `json:"notification_id" valid:"required"`
+}
+
+// MarkSeenResponse represents the response from marking a notification as seen
+type MarkSeenResponse struct {
+	Status string `json:"status"`
+}