[sylvainsf]

Description

Adds onto #12250 the two items the Repo Radius feature spec requires for
Investment 3 that aren't in the deploy workflow yet: the radius_commands
dispatch contract and a technical design note. Targets the
add-deploy-workflow branch so it folds into #12250.

What this adds

radius_commands dispatch input (additive — image unchanged)

The feature spec (Step 3, Investment 3) defines the workflow's dispatch contract as
environment + radius_commands: a single rad command string, or a JSON array of
command strings run in order (the rad prefix omitted), so a frontend can drive
arbitrary rad commands — not only a single deploy.

This adds radius_commands as an optional input alongside the existing image:

• When radius_commands is set, the workflow runs each command in order, stops on
  the first failure, and uploads each command's output as the radius-output
  artifact for incremental frontend polling (spec Step 5).
• When it's empty, the workflow runs its existing default rad deploy of
  .radius/app.bicep with the image/password parameters — current behavior is
  unchanged.

This keeps the convenient single-deploy path while making the documented
multi-command contract available to frontends (Copilot app, CLI, etc.).

Technical design note

eng/design-notes/environments/2026-06-repo-radius-deploy-workflow.md — the design
doc Nicole requires for this feature. It documents Investments 3 & 4: the dispatch
contract, the RADIUS_TARGET_KUBECONFIG seam, the UCP-credential + projected-OIDC-
token model (AWS IRSA / Azure WI), state persistence, and the recipe-pack /
image-build flow as implemented in #12250.

Notes

• Co-authored design note (sk593 + sylvainsf) reflecting the Add deploy workflow #12250 implementation,
  not the earlier prototype.
• The radius-output artifact uses the same SHA-pinned upload-artifact already in
  the workflow.

Type of change

• This pull request adds or changes features of Radius and has an approved issue (issue link required).

Related: #12118
Builds on: #12250

Contributor checklist

• An overview of proposed schema changes is included in a linked GitHub issue.
  • Yes
  • Not applicable
• A design document is added or updated under eng/design-notes/ in this repository, if new APIs are being introduced.
  • Yes
  • Not applicable
• The design document has been reviewed and approved by Radius maintainers/approvers.
  • Yes
  • Not applicable
• A PR for resource-types-contrib is created, if resource types or recipes are affected by the changes in this PR.
  • Yes
  • Not applicable
• A PR for dashboard is created, if the Radius Dashboard is affected by the changes in this PR.
  • Yes
  • Not applicable
• A PR for the documentation repository is created, if the changes in this PR affect the documentation or any user facing updates are made.
  • Yes
  • Not applicable

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[Copilot]

Pull request overview

This PR extends the Repo Radius deploy workflow template by formalizing the radius_commands dispatch contract (to support running one or more arbitrary rad commands) and adds a technical design note documenting the end-to-end deploy workflow design and its integration seams.

Changes:

• Add optional radius_commands workflow_dispatch input to run either a single rad command string or a JSON array of commands, capturing output for artifact upload.
• Capture command output into /tmp/radius-output and upload it as a radius-output artifact (plus update default deploy logging to tee into the same output directory).
• Add eng/design-notes/environments/2026-06-repo-radius-deploy-workflow.md describing Investments 3/4, workflow stages, and contracts.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
.github/extension/radius-deploy.yml	Adds radius_commands input and a command-execution path that captures stdout/stderr and uploads radius-output.
eng/design-notes/environments/2026-06-repo-radius-deploy-workflow.md	Adds a design note documenting the workflow’s dispatch contract, kubeconfig seam, credential model, and state persistence.