[ECR] [Image Users]: Build a service to allow users to check whether root user is enabled on images in ECR.

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**Tell us about your request**
Enhance Amazon ECR with a built-in capability to detect if container images have the root user enabled.

**Which service(s) is this request for?**
ECR

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
Currently, there's no direct method to determine if a container image in ECR uses the root user. While tools like image scanners can provide insights, they often require additional configuration and don't offer a comprehensive solution.

The challenge lies in the static nature of container images. ECR primarily focuses on storage and distribution, lacking the capacity to analyze image content for security implications like root user usage.

**Are you currently working around this issue?**
To mitigate this issue, we're currently implementing a combination of approaches:

Dockerfile analysis: Manually reviewing Dockerfiles to ensure non-root user configuration.
Runtime checks: Monitoring running containers for root user activity.
However, these methods are time-consuming, error-prone, and lack a centralized view of root user usage across our ECR repositories.

**Additional context**
Having a built-in root user detection feature in ECR would significantly enhance container image security. It would streamline the process of identifying potential vulnerabilities, improve compliance efforts, and reduce the risk of unauthorized actions.

By providing actionable insights into image configuration, AWS can help customers strengthen their container security posture and prevent potential security breaches.

**Attachments**
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The issue names no repository files, tests, or entry points; begin by reviewing the ECR roadmap context and existing image-analysis or security capabilities. Clarify the intended detection behavior and scope, with done defined as an ECR capability that reports whether images have root enabled.

Written by the indexing model from the issue text.