improve benchmark reporting

[jankdc]

No description provided.

[github-actions]

Bench report

Common-op timings on ubuntu-24.04:

array-of-objects, memory source, n=100,000, cap=256.

operation	bote	JSON.parse	bote/parse
get · shallow	33.2 µs	38.53 ms	0.00085x
get · deep	1.08 ms	38.03 ms	0.028x
has · shallow	32.7 µs	38.30 ms	0.00084x
walk · walk-all	33.8 µs/item	38.14 ms	88.63x
iter · iter-all	35.5 µs/item	37.88 ms	93.73x
walk · walk-get-name	66.1 µs/item	50.44 ms	131.13x