AWS::ECR::Repository - [Enhancement] - Return dual-stack URI

### Name of the resource

AWS::ECR::Repository

### Resource name

_No response_

### Description

ECR recently added support for dual-stack endpoints: https://docs.aws.amazon.com/AmazonECR/latest/userguide/ecr-requests.html#ecr-requests-from-docker-cli

It would be helpful if the dual-stack repository URI was made available as a return value for AWS::ECR::Repository resources.

### Other Details

_No response_

Read the linked AWS ECR dual-stack endpoint documentation and the AWS::ECR::Repository resource details first. The issue provides no repository files, tests, or entry points; completion would require making the dual-stack repository URI available as a return value and verifying that behavior.

Written by the indexing model from the issue text.