Add CodSpeed benchmark workflow

[BartWaardenburg]

Summary

• Add a CodSpeed simulation workflow for the Rust benchmark shards.
• Convert the Rust benchmark harnesses from Criterion to the CodSpeed Divan compatibility crate.
• Download real-world sourcemap fixtures for the sourcemap benchmark shard.

Validation

• cargo fmt --all --check
• cargo clippy --workspace --all-targets -- -D warnings
• cargo bench --workspace --no-run
• cargo test --workspace
• node benchmarks/download-fixtures.mjs
• cargo codspeed build for the workflow shards
• cargo bench ... -- --test for the converted benchmark targets
• actionlint .github/workflows/bench.yml

[codspeed-hq]

Congrats! CodSpeed is installed 🎉

🆕 76 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

• from_parts_interop_medium_from_parts: 596.8 µs
• from_parts_interop_medium_json_roundtrip: 2.1 ms
• from_parts_interop_small_from_parts: 41.7 µs
• from_parts_interop_small_json_roundtrip: 135 µs
• json_only_serde_json_minimal: 658 µs
• json_only_serde_json_value: 1.4 ms
• json_only_simd_json_minimal: 2.7 ms
• json_only_sonic_rs_minimal: 546.2 µs
• lite_paths_chartjs_lazy_fast: 4.8 ms
• lite_paths_chartjs_lazy_no_content: 9.2 ms
• lite_paths_chartjs_no_content: 8.7 ms
• lite_paths_pdfjs_lazy_fast: 20.2 ms
• lite_paths_pdfjs_lazy_no_content: 42.8 ms
• lite_paths_pdfjs_no_content: 48.1 ms
• lite_paths_preact_lazy_fast: 343.9 µs
• lite_paths_preact_lazy_no_content: 525.1 µs
• lite_paths_preact_no_content: 512.9 µs
• lookup_1000x_original_position_for: 132.3 µs
• lookup_single_original_position_for: 601.7 ns
• parse_backends_large_current: 9.8 ms
• ...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.

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