feat: add push notification settings to user profile and update related functionality

backend/api/user_api.py

@@ -48,6 +48,7 @@ def get_profile():
         'email': user.email,
         'image_id': user.image_id,
         'email_digest_enabled': user.email_digest_enabled,
+        'push_notifications_enabled': user.push_notifications_enabled,
     }), 200
 
 @user_api.route('/user/profile', methods=['PUT'])
@@ -59,11 +60,12 @@ def update_profile():
     if not user:
         return jsonify({'error': 'Unauthorized'}), 401
     data = request.get_json()
-    # Only allow first_name, last_name, image_id, email_digest_enabled to be updated
+    # Only allow first_name, last_name, image_id, email_digest_enabled, push_notifications_enabled to be updated
     first_name = data.get('first_name')
     last_name = data.get('last_name')
     image_id = data.get('image_id')
     email_digest_enabled = data.get('email_digest_enabled')
+    push_notifications_enabled = data.get('push_notifications_enabled')
     if first_name is not None:
         user.first_name = first_name
     if last_name is not None:
@@ -72,6 +74,8 @@ def update_profile():
         user.image_id = image_id
     if email_digest_enabled is not None:
         user.email_digest_enabled = bool(email_digest_enabled)
+    if push_notifications_enabled is not None:
+        user.push_notifications_enabled = bool(push_notifications_enabled)
     users_db.update(user.to_dict(), UserQuery.email == user.email)
     
     # Create tracking event
@@ -84,6 +88,8 @@ def update_profile():
         metadata['image_updated'] = True
     if email_digest_enabled is not None:
         metadata['email_digest_enabled_updated'] = True
+    if push_notifications_enabled is not None:
+        metadata['push_notifications_enabled_updated'] = True
     
     tracking_event = TrackingEvent.create_event(
         user_id=user_id,