Add CodSpeed continuous benchmarking

[codspeed-hq]

Summary

This PR sets up CodSpeed to continuously measure the performance of Sury in CI, so performance regressions are caught automatically on every pull request.

The repository already had a benchmark.js suite in packages/e2e (Benchmark.res). This integration reuses that suite directly rather than introducing a parallel one.

Changes

• Benchmark harness: Wrapped the existing benchmark.js Suite with withCodSpeed from @codspeed/benchmark.js-plugin. The change is applied to both the ReScript source (Benchmark.res) and its committed generated output (Benchmark.res.mjs) so they stay in sync. When not running under CodSpeed, the suite behaves exactly as before.
• Dependency: Added @codspeed/benchmark.js-plugin as a dev dependency of packages/e2e (lockfile updated).
• CI workflow: Added .github/workflows/codspeed.yml. It installs dependencies with pnpm and runs the benchmarks through CodSpeedHQ/action@v4 in simulation mode, using OIDC authentication. It triggers on pushes to main, on pull requests, and via workflow_dispatch (to let CodSpeed generate baseline data).
• README: Added the CodSpeed badge.

Validation

The setup was verified locally with the CodSpeed CLI:

codspeed run --mode simulation -- node ./src/benchmark/Benchmark.res.mjs

All 19 benchmarks were measured and reported successfully under CPU simulation.

Notes

• The benchmarks run on the standard ubuntu-24.04 GitHub-hosted runner, consistent with the existing CI. Simulation mode is hardware-agnostic, so no specialized runners are required.
• Once this is merged and CodSpeed has baseline data, performance reports will appear directly on pull requests.

Next steps

• Merge this PR so CodSpeed can collect a performance baseline from main.
• Review subsequent PRs for the automatic CodSpeed performance report.

[codspeed-hq]

Congrats! CodSpeed is installed 🎉

🆕 19 new benchmarks were detected.

You will start to see performance impacts in the reports once the benchmarks are run from your default branch.

Detected benchmarks

• S.object - make: 95.8 µs
• S.object - make + parse: 318.8 µs
• S.object - make + reverse: 144.5 µs
• S.object - make + reverse convert: 357.7 µs
• S.object - parse: 24.5 µs
• S.schema - assert (compiled): 16.1 µs
• S.schema - assert strict: 27.8 µs
• S.schema - make: 35.2 µs
• S.schema - make + parse: 287.5 µs
• S.schema - make + reverse: 61.2 µs
• S.schema - make + reverse convert: 196.7 µs
• S.schema - parse: 26.3 µs
• S.schema - parse strict: 27.7 µs
• S.schema - reverse convert: 24.4 µs
• S.schema - reverse convert (compiled): 6.9 µs
• S.object - reverse convert: 26.4 µs
• S.schema - assert: 27.3 µs
• S.string - parse: 22 µs
• S.string - reverse convert: 22.7 µs

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[github-actions]

Benchmark

Details

Benchmark suite	Current: 3fece52	Previous: c54107f	Ratio
S.schema - make	2536465 ops/sec (±0.56%)	2398575 ops/sec (±1.23%)	0.95
S.schema - make + parse	53692 ops/sec (±5.32%)	29310 ops/sec (±6.48%)	0.55
S.schema - parse	4790734 ops/sec (±0.77%)	4274227 ops/sec (±0.48%)	0.89
S.schema - parse strict	4496380 ops/sec (±0.66%)	3741471 ops/sec (±0.44%)	0.83
S.schema - make + reverse	376892 ops/sec (±1.43%)	365460 ops/sec (±0.55%)	0.97
S.schema - make + reverse convert	81054 ops/sec (±0.85%)	46515 ops/sec (±0.63%)	0.57
S.schema - reverse convert	3681953 ops/sec (±0.61%)	2878997 ops/sec (±0.35%)	0.78
S.schema - reverse convert (compiled)	128554446 ops/sec (±6.69%)	131756222 ops/sec (±3.83%)	1.02
S.schema - assert	3392020 ops/sec (±0.53%)	3111535 ops/sec (±0.71%)	0.92
S.schema - assert (compiled)	70045353 ops/sec (±2.56%)	69843432 ops/sec (±2.09%)	1.00
S.schema - assert strict	2816347 ops/sec (±0.81%)	2542963 ops/sec (±0.50%)	0.90
S.object - make	435091 ops/sec (±0.34%)	431984 ops/sec (±0.19%)	0.99
S.object - make + parse	42353 ops/sec (±1.64%)	21529 ops/sec (±1.64%)	0.51
S.object - parse	4989267 ops/sec (±0.44%)	4452364 ops/sec (±0.76%)	0.89
S.object - make + reverse	65185 ops/sec (±0.61%)	63926 ops/sec (±0.15%)	0.98
S.object - make + reverse convert	30533 ops/sec (±1.85%)	19297 ops/sec (±1.80%)	0.63
S.object - reverse convert	3421609 ops/sec (±0.59%)	2847176 ops/sec (±0.60%)	0.83
S.string - parse	6295137 ops/sec (±0.33%)	5236562 ops/sec (±0.55%)	0.83
S.string - reverse convert	5245659 ops/sec (±0.99%)	4410046 ops/sec (±0.98%)	0.84

This comment was automatically generated by workflow using github-action-benchmark.