Amplify CLI XR Plugin

The `amplify-category-xr` package, currently at version `3.4.4` as per the provided metadata, extends the AWS Amplify Command Line Interface (CLI) to allow developers to provision and manage cloud resources for Extended Reality (XR) applications. This typically included services for AR/VR/MR capabilities within Amplify-powered backends. As part of the broader AWS Amplify CLI monorepo, its release cadence historically aligned with frequent updates for bug fixes and minor features across the CLI. However, this plugin's core functionality is now deprecated as its underlying dependency, Amazon Sumerian, is no longer accepting new customers, and existing Sumerian scenes were slated to be unavailable after February 21, 2023. Therefore, while the CLI plugin exists, it no longer provisions functional resources. Its original key differentiator was abstracting complex AWS service configurations for XR, integrating with other Amplify categories like Auth and Storage.