Adds DPO and SFT to CI and combines push-image with beaker-experiment

[finbarrtimbers]

Ran manually: https://github.com/allenai/open-instruct/actions/runs/19119030962

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Note

Builds and verifies an integration image, launches GRPO always plus DPO/SFT experiments conditionally, waits in parallel, then pushes the image to Beaker; removes old push workflow/action and adds DPO/SFT test scripts.

• CI/Workflows:
  • Beaker Experiment (.github/workflows/beaker-experiment.yml):
    • Build integration Docker image, detect changed files, and conditionally launch experiments (grpo always; dpo/sft when relevant files change).
    • Capture experiment IDs, wait for all in parallel with timeouts, stream error logs on failure, and summarize results.
    • Verify/pull branch-tagged integration image and push final image (open_instruct_auto) to Beaker.
    • Updates: Python 3.12, Beaker workspace ai2/open-instruct-dev.
  • Remove legacy image workflow and action: delete ./.github/workflows/push-image.yml and ./.github/actions/push/action.yaml.
• Actions:
  • Update setup action workspace (.github/actions/setup/action.yaml) to ai2/open-instruct-dev.
• Scripts:
  • Add scripts/train/debug/dpo_integration_test.sh and scripts/train/debug/sft_integration_test.sh for CI experiment launches.

^{Written by Cursor Bugbot for commit edd6ac2. This will update automatically on new commits. Configure here.}

[cursor]

Bug: Workflow Triggers: Incomplete Event Data

The trigger_info output is not set for merge_group events, but the workflow triggers on merge_group. The step only handles push and workflow_dispatch events, leaving trigger_info undefined when triggered by merge groups, which results in an empty trigger description in the summary.