[WIP] Add optional deterministic pre-compute step for workflows

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

Original prompt

Suggest a way to optionally insert a deterministic pre-compute step for agentic workflows if needed (like the discover phase on campaigns) and be guided by regular actions syntax:

jobs:
  job1:
    runs-on: ubuntu-latest
    outputs:
      message: ${{ steps.out.outputs.msg }}
    steps:
      - id: out
        run: echo "msg=Hello from job1" >> "$GITHUB_OUTPUT"

  job2:
    runs-on: ubuntu-latest
    needs: job1
    steps:
      - name: Use output from job1
        run: echo "${{ needs.job1.outputs.message }}"

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[mnkiefer]

• Not needed