Criterion benchmark for recordbatches_to_timeseries in
src/servers/src/prom_store.rs,
the function that turns a columnar RecordBatch into Prometheus TimeSeries.
Used to measure GreptimeTeam/greptimedb#8587
(perf(servers): optimize PromQL read conversion). Not part of the repository —
kept here so the numbers in the blog post are reproducible.