chore: Remove legacy testing.yml (duplicate of checks.yml)

[ashleyshaw]

Chore Summary

The .github/workflows/testing.yml workflow is a legacy duplicate of checks.yml. Running this workflow wastes ~2-3% of monthly GitHub Actions minutes by duplicating CI checks. Removing testing.yml entirely will consolidate CI infrastructure, as checks.yml is the authoritative CI workflow and covers all validation needs.

Scope / Affected Areas

• .github/workflows/testing.yml — legacy duplicate workflow file
• Project documentation and references to testing.yml
• CI validation coverage verification

Steps / Checklist

• Audit confirms testing.yml duplicates checks.yml
• No external repos reference this workflow
• checks.yml covers all required test scenarios
• Delete .github/workflows/testing.yml
• Search docs for any references to testing.yml
• Update any references to point to checks.yml
• Verify checks.yml has all necessary validations
• Create PR and request review
• Merge to develop

Acceptance Criteria

• File .github/workflows/testing.yml is deleted
• Git history shows clean file deletion
• No documentation references to testing.yml remain
• Verified no external repos depend on this workflow
• checks.yml still covers all test scenarios
• PR merged to develop

Additional Context

• Parent Epic: feat: Consolidate 31 GitHub workflows for efficiency and maintainability #1227 - Consolidate 31 GitHub workflows
• Project Documentation: .github/projects/active/workflows-consolidation-2026-q3/README.md
• Phase 1A Guide: .github/projects/active/workflows-consolidation-2026-q3/GITHUB_ISSUE_PHASE_1A.md
• Execution Playbook: .github/projects/active/workflows-consolidation-2026-q3/EXECUTION_PLAYBOOK.md

Effort: 1 hour | Phase: 1A - Quick Wins

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Definition of Ready (DoR)

• Audit confirms testing.yml duplicates checks.yml
• No external repos reference this workflow
• checks.yml covers all required test scenarios

Definition of Done (DoD)

• Affected files and documentation updated
• PR uses correct branch prefix (chore/)
• Approved by at least one maintainer
• Code changes follow repository style guidelines
• No breaking changes
• Manual verification: Workflows still trigger as expected

---

Definition of Ready (DoR)

• Task clearly defined
• Acceptance criteria listed
• Related issues linked
• Estimated effort

Definition of Done (DoD)

• Task completed
• Changes reviewed and merged
• No regressions introduced
• Documentation updated if needed

[linear-code]

LS-1778

[github-actions]

⏱️ Aging and SLA annotation

• Age: 0 day(s)
• SLA state: Within SLA
• Thresholds: warn at 7 days, breach at 14 days
• Last updated: 2026-07-24T06:21:58.605Z

Maintained by project-meta-sync workflow.