Two benches for reading side by side before and after a change, against a
copy of a real catalog, in the manner of identity_bench:
- `dr-catalog --example catalog_bench CATALOG [FACES_DIR]` times
`Catalog::open` and the backfill inside it step by step, the upload
snapshot, a merge of the catalog with a copy of itself, and the face
shard export and import in the steady state where nothing is new.
- `persist_bench`, an ignored test in dr-ui's scan module because
`persist` and `apply_judgement` are private to it, replays the
catalog's own rows through `persist` (the largest folder, and the whole
library) and looks up every `.drsc` sidecar the catalog has read. It
works on a scratch copy and prints a fingerprint of what `persist` left,
so two builds can be shown to agree.
Both print best, median and CPU time; the CPU figure is the one to compare
while other builds share the machine.