CI: benchmark regression detection on PR #140
Description
Problem
Performance regressions can slip in undetected without automated comparison.
Sub-tasks
- GitHub Actions workflow running BenchmarkDotNet on PRs
- Compare against baseline stored in repo (or previous run)
- Post results as PR comment (e.g., via
benchmark-action/github-action-benchmark) - Warning threshold (not hard gate) for regressions > 5%
Dependencies
Depends on: #134 (full benchmark suite)
Unlocks: performance regression protection
Phase
Phase 4 (Polish & Release Readiness)