Specify the AWS experience for Radius in GitHub Copilot App Canvas

Type: PM + Engineering

Overview of feature request

Define the supported AWS workflows and user experience for managing and deploying Radius applications through the GitHub Copilot App Canvas.

The specification should establish the intended parity with Azure, identify intentional differences, and define the boundary between Canvas, generated GitHub Actions workflows, Radius environments, and AWS infrastructure.

Acceptance criteria

• Supported AWS target platforms are identified, including whether the initial scope includes EKS, EKS Auto Mode, and ECS.
• The end-to-end user journeys for credential setup, verification, application modeling, deployment, status reporting, and troubleshooting are documented.
• Required AWS authentication and authorization mechanisms are defined, including GitHub Actions OIDC, IAM roles, and least-privilege expectations.
• The inputs, outputs, validation behavior, and actionable error messages for each Canvas step are specified.
• Azure parity requirements and intentional AWS-specific differences are documented.
• Security, telemetry, documentation, and compatibility requirements are documented.
• Follow-up engineering issues are created or updated for each independently deliverable capability.

Additional context

Related to #12724. Coordinate this decision with the long-term direction for AWS and Azure support in UCP so Canvas does not depend on an integration path that Radius intends to remove or deprecate.

Start by reading related issue #12724 and reviewing the long-term AWS and Azure direction for UCP. Define the supported AWS targets, Canvas and Radius boundaries, authentication and deployment journeys, parity differences, and follow-up engineering issues; done means all listed acceptance criteria are documented and independently deliverable work is tracked.