Fix cross-repo workflow_call integrity check: use github.workflow_ref instead of GITHUB_WORKFLOW_REF (#24200)

* Initial plan

* fix: use github.workflow_ref context to fix remote workflow_call integrity check

For cross-repo workflow_call invocations, GITHUB_WORKFLOW_REF env var points to
the top-level caller's workflow, not the reusable (callee) workflow. This caused
check_workflow_timestamp_api.cjs to look for lock files in the wrong repository.

The fix injects GH_AW_CONTEXT_WORKFLOW_REF from ${{ github.workflow_ref }} which
correctly identifies the current reusable workflow even in cross-repo scenarios.

Closes #23935

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* test: add same-repo scenario tests for GH_AW_CONTEXT_WORKFLOW_REF coverage

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* fix: align CJS error messages with main branch to fix CI test failures

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* merge: merge main and recompile all lock files

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* fix: rename 'Check workflow file timestamps' step to 'Check workflow lock file'

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: pelikhan <4175913+pelikhan@users.noreply.github.com>
Co-authored-by: Peli de Halleux <pelikhan@users.noreply.github.com>

Author: Copilot