Auto-assign Copilot to github/github-ui after release issue creation

[Copilot]

Automates Copilot assignment for integration work when new @primer/react-brand releases are detected.

Changes

• Added workflow step using gh agent-task create to assign Copilot in github/github-ui
• Task includes release name, release URL, and link to tracking issue
• Uses continue-on-error: true to prevent blocking the primary issue creation workflow

- name: Assign Copilot to perform integration work
  if: success()
  continue-on-error: true
  env:
    GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
  run: |
    gh agent-task create \
      -R github/github-ui \
      "Upgrade @primer/react-brand to ${{ steps.get_latest_release.outputs.release_name }}. ..."

Original prompt

Update the create issue workflow to automatically assign the issue to @copilot after it is created. Copilot will need to perform the work in the github/github-ui repo, so make sure that is included when assigning. The GitHub CLI 'agent-task' might be useful for this.

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[dustinbrownman]

@copilot Why is the GITHUB_UI token necessary. We should be able to use the existing token that is part of this workflow.

[Copilot]

@copilot Why is the GITHUB_UI token necessary. We should be able to use the existing token that is part of this workflow.

Updated to use GITHUB_TOKEN in d84c3e2.

[dustinbrownman]

@rezrah - Curious to get your thoughts on this. It's small step, but shortcutting the work of making the change, pushing, and creating a PR seems valuable. Then our First Responder can focus on validating the necessary pages via a preview deploy.

[Copilot]

Pull request overview

This PR automates Copilot agent assignment for integration work when new @primer/react-brand releases are detected, streamlining the upgrade process in the github/github-ui repository.

Key Changes:

• Added a workflow step that creates a Copilot agent task in the github/github-ui repository
• Includes release metadata (name, URL) and a link to the tracking issue in the task description
• Uses continue-on-error: true to ensure the Copilot assignment doesn't block the primary workflow

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[rezrah]

@dustinbrownman this is a cool idea. A few thoughts:

• Will this work in practice? GITHUB_TOKEN is usually scoped to the repo, so will CCA have sufficient permissions to begin working on this task in a private repo in the GitHub org (noting that this is the Primer org). I suspect we'll run into both Cross-Org + Cros-Repo auth issues here, but correct me if I'm wrong.

• Some releases will contain breaking changes, or require manual updates to UI code in addition to the node_module upgrade. We need Copilot to carefully read the changelog entries and apply updates as described. Can we either expand the description/prompt or use the --custom-agent param to specify more granular instructions for the agent to follow. I'm mostly calling out that node_module updates alone aren't going to be enough.