Add post-run automation callbacks

[malhotra5]

Summary

Implements post-run automation callbacks for APP-2489 / #208 using the callback-chain design.

• Adds durable automation_run_callbacks records with persisted callback lifecycle state.
• Adds automation-level callbacks config with exactly-one-of validation for entrypoint vs inline_python.
• Defaults automations with callbacks to keep_alive=True when keep_alive is omitted, so normal sandbox cleanup can be left to runtime TTL/reaper.
• Materializes preset inline_python callbacks into generated tarballs under callbacks/<name>.py and normalizes them to callback entrypoints.
• Schedules callbacks when runs reach COMPLETED or FAILED via either SDK completion callback or watchdog verification.
• Starts one in-sandbox Python wrapper command that runs matching callbacks sequentially in the existing workdir, captures per-callback results, and POSTs a final completion payload back to the automation service.
• Adds POST /runs/{run_id}/callbacks/complete for the wrapper completion payload and GET /runs/{run_id}/callbacks for inspecting callback records.
• Keeps explicit cleanup blocked until callbacks have been dispatched; if keep_alive=False is explicitly used, callback completion can clean up after terminal callback records.

Testing

• uv run pre-commit run --files openhands/automation/models.py openhands/automation/schemas.py openhands/automation/preset_router.py openhands/automation/router.py openhands/automation/watchdog.py openhands/automation/app.py openhands/automation/backends/base.py openhands/automation/backends/cloud.py openhands/automation/backends/local.py openhands/automation/callbacks.py migrations/versions/010_post_run_callbacks.py tests/test_callbacks.py tests/test_schemas.py tests/test_preset_router.py --show-diff-on-failure
• uv run pytest tests/test_callbacks.py tests/test_schemas.py tests/test_preset_router.py::TestGenerateTarball -q

Note: tests/test_watchdog.py could not be run in this environment because the Docker daemon is unavailable and the test fixture starts a Postgres testcontainer before executing tests.

Closes #208
Linear: APP-2489

This PR description was updated by an AI agent (OpenHands) on behalf of the user.

[github-actions]

[all-hands-bot]

👋 This PR needs a couple of things fixed before OpenHands can review it:

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[all-hands-bot]

Required CI has remained failing for seven days. Please repair it or comment with an update. If the author does not push or comment and required CI remains failing for another seven days, this pull request will be closed automatically.

[all-hands-bot]

Closing because required CI is still failing seven days after the automated warning and the author has not pushed or commented. The pull request can be reopened when work resumes.