fix(ci): remove duplicate clang-format check

[mvillmow]

Summary

Resolves #260 by removing the duplicate clang-format check from the quality CI job.

The quality job was running two overlapping formatting checks:

1. just format-check (uses system clang-format version)
2. pre-commit action (uses pinned v18.1.0)

This could cause false conflicts where one passes and the other fails due to version differences. By removing the Make-based check, we establish the pre-commit hook (v18.1.0) as the single source of truth for C++ formatting validation.

Changes

• Removed the "Check formatting" step from the quality job in .github/workflows/ci.yml
• Pre-commit continues to enforce clang-format v18.1.0 as configured in .pre-commit-config.yaml

Testing

• ✅ Verified just format-check still works locally for developers
• ✅ Pre-commit hook remains active for CI validation

Generated with Claude Code

[github-actions]

✅ Dependency Audit

Severity	Count
Critical	0
High	0
Medium	0
Low	0

See the Security tab for detailed findings.

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Workflow: Dependency Audit

[github-actions]

Security Scan Results

• ❌ Secret Scanning: Potential secrets found
• ✅ SAST: Completed (check Security tab for details)
• ✅ Dependency Scanning: Completed
• ✅ C++ Static Analysis: Completed
• ✅ Docker Image Scanning: 0 high, 22 medium vulnerabilities (acceptable)

Recommendations

• Review findings in the GitHub Security tab
• Check artifact uploads for detailed reports
• Address critical Docker vulnerabilities immediately

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Workflow: Security Scanning

[mvillmow]

Superseded — this PR removed a duplicate clang-format check from .github/workflows/ci.yml, but ci.yml was deleted on main in commit 6dd4bf7 (CI consolidated into _required.yml). The fix is no longer applicable. Closing.