ci(babysitter): switch from check_run to workflow_run trigger

[pzelasko]

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What does this PR do ?

The PR Babysitter never investigated real CI failures. Check-runs produced by GHA jobs authenticated with the default GITHUB_TOKEN do not fire check_run events on downstream workflows (GitHub's recursion guard). As a result, check-label-for-ci skipped on every CI failure it was meant to handle — verified on PR #15626 where all 31 recent check_run-triggered runs skipped every job despite multiple failing checks (Nemo_CICD_Test, Nemo_Linting_Test, etc.).

Replace the check_run: [completed] trigger with an explicit workflow_run: [completed] list covering the CI workflows that can fail on a PR (CICD NeMo, PyLint/flake8, wheel build, init check, copyright, CI-Install-Check, CodeQL, secrets detector). Intentionally omitted: "Isort and Black Formatting" (auto-pushes fixes), the babysitter itself, and labeler/relabel bots.

Update check-label-for-ci, the investigate prompt, and ping-author-on-failure to read github.event.workflow_run.* instead of github.event.check_run.* (conclusion, pull_requests, head_sha, name). Drop the reformat_with_isort_and_black name filter — filtering is now done at the trigger level by not listing that workflow.

Semantics change: one investigation per failing workflow (not per failing check). The existing prompt already instructs Claude to look at all failing checks on the PR, so coverage is unchanged and the noise is lower.

Collection: CI

Changelog

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Usage

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GitHub Actions CI

The Jenkins CI system has been replaced by GitHub Actions self-hosted runners.

The GitHub Actions CI will run automatically when the "Run CICD" label is added to the PR.
To re-run CI remove and add the label again.
To run CI on an untrusted fork, a NeMo user with write access must first click "Approve and run".

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• Make sure you read and followed Contributor guidelines
• Did you write any new necessary tests?
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PR Type:

• New Feature
• Bugfix
• Documentation

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Additional Information

• Related to # (issue)