AWS - Sample example with DynamoDB

We need a sample application that uses DynamoDB in its environment definition.

https://github.com/cloud-ark/cloudark-samples

Start by reviewing the linked cloudark-samples repository and the caastle configuration that defines sample environments. Identify how existing sample applications declare external services, then determine the expected DynamoDB environment definition and application behavior. Done means a working sample application using DynamoDB is included and can be deployed through the documented environment definition.

Written by the indexing model from the issue text.