ci(release): add release-main workflow for develop promotion via gitutils

[Copilot]

Adds a dedicated release-main workflow to automate the release flow requested in the issue: instantiate tomgrv/devcontainer-features/gitutils and run git beta && git prod from develop.

• Workflow: release-main

  • New file: .github/workflows/release-main.yml
  • Triggers on:
    • push to develop
    • workflow_dispatch

• Release execution path

  • Checks out full history from develop (fetch-depth: 0, ref: develop)
  • Sets up Node runtime via tomgrv/actions/setup-node@v0
  • Installs GitUtils with npx tomgrv/devcontainer-features -- gitutils
  • Configures bot git identity
  • Executes release sequence: git beta && git prod

• Safety/diagnostic guards

  • Verifies GitUtils-provided aliases (alias.beta, alias.prod) before running release commands
  • Emits explicit failure messages when installation or alias provisioning is not available

- name: Install GitUtils
  run: npx tomgrv/devcontainer-features -- gitutils

- name: Verify GitUtils aliases
  run: |
    git config --global --get alias.beta >/dev/null || { echo 'Missing git beta alias after GitUtils install; check the "Install GitUtils" step logs.'; false; }
    git config --global --get alias.prod >/dev/null || { echo 'Missing git prod alias after GitUtils install; check the "Install GitUtils" step logs.'; false; }

- name: Run git beta then git prod
  env:
    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
  run: git beta && git prod