feature: Support for IAM Identity Center shortcut links

[niallthomson]

🔖 Feature description

There are already situations where we provide deep links to specific screens within the AWS console from Backstage plugins, such as the specific CodePipeline executions or CodeBuild project builds. It is expected that we will continue to add more of these in the interest of avoiding re-producing all AWS console information in Backstage.

However providing these deep links to the AWS console can be tricky in a situation where multiple AWS accounts are involved since the console does not have a mechanism to switch accounts. This means the existing links will not properly account for cross-account situations where the user is not logged in to the appropriate account.

The new shortcut link feature for IAM Identity Center lets you construct links via the access portal that point to specific AWS accounts. This would at least allow users leveraging Identity Center to provide better link capabilities in their Backstage portal.

🎤 Context

Shortcut links documentation:

https://aws.amazon.com/about-aws/whats-new/2024/04/aws-iam-identity-center-shortcut-links-aws-access-portal/

✌️ Possible Implementation

This feature would need to be optional and probably packaged as a utility function in a core package.

To construct a link with this feature it would need to be aware of the Identity Center portal domain (for example your_subdomain.awsapps.com) and parameters would be the target account ID and full link to the particular screen in the AWS console (for example https://us-west-2.console.aws.amazon.com/s3/buckets/my-bucket-name).