ci: add benchmark workflow

.github/scripts/run_benchmarks.sh

@@ -0,0 +1,69 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+mkdir -p benchmark-results
+benchmark_json="${BENCHMARK_JSON:-benchmark-results/current.json}"
+benchmark_root="$(dirname "$benchmark_json")"
+hyperfine_benchmark_dir="${BENCHMARK_HYPERFINE_DIR:-tests/benchmarks/hyperfine}"
+pytest_benchmark_dirs="${BENCHMARK_PYTEST_DIRS:-${BENCHMARK_PYTEST_DIR:-}}"
+benchmark_work_dir="$benchmark_root/raw-results"
+hyperfine_json_dir="$benchmark_work_dir/hyperfine"
+pytest_json="$benchmark_work_dir/pytest.json"
+
+shopt -s nullglob
+benchmark_scripts=()
+benchmark_scripts=("$hyperfine_benchmark_dir"/benchmark_*.sh)
+shopt -u nullglob
+
+pytest_dirs=()
+for pytest_benchmark_dir in $pytest_benchmark_dirs; do
+  if [ -d "$pytest_benchmark_dir" ]; then
+    pytest_dirs+=("$pytest_benchmark_dir")
+  else
+    echo "Pytest benchmark directory not found: $pytest_benchmark_dir" >&2
+    exit 1
+  fi
+done
+
+if [ "${#benchmark_scripts[@]}" -eq 0 ] && [ "${#pytest_dirs[@]}" -eq 0 ]; then
+  echo "No benchmark scripts or pytest benchmarks found" >&2
+  exit 1
+fi
+
+echo "Benchmark Python: $(command -v python)"
+python -c 'import sys; print(sys.version)'
+
+rm -rf "$benchmark_work_dir"
+mkdir -p "$hyperfine_json_dir"
+
+if [ "${#benchmark_scripts[@]}" -gt 0 ]; then
+  for benchmark_script in "${benchmark_scripts[@]}"; do
+    title="$(sed -n 's/^# BENCHMARK_TITLE:[[:space:]]*//p' "$benchmark_script" | head -n 1)"
+    if [ -z "$title" ]; then
+      title="$(basename "$benchmark_script" .sh)"
+    fi
+    benchmark_name="$(basename "$benchmark_script" .sh)"
+    benchmark_result_json="$hyperfine_json_dir/$benchmark_name.json"
+    echo "Preflight benchmark script: $benchmark_script"
+    bash "$benchmark_script"
+
+    hyperfine \
+      --show-output \
+      --warmup 1 \
+      --runs 5 \
+      --command-name "$title" \
+      --export-json "$benchmark_result_json" \
+      "bash $(printf "%q" "$benchmark_script")"
+  done
+fi
+
+if [ "${#pytest_dirs[@]}" -gt 0 ]; then
+  pytest \
+    -q "${pytest_dirs[@]}" \
+    --benchmark-only \
+    --benchmark-json "$pytest_json"
+fi
+
+python .github/scripts/aggregate_benchmarks.py \
+  --input-dir "$benchmark_work_dir" \
+  --output "$benchmark_json"