chore: move benchmarking script to this repo

[Kha]

Corresponding to Kha/lean-bench@d3f39f8

[Kha]

!bench

[leanprover-bot]

Here are the benchmark results for commit 7bef7f0.
The entire run failed.
Found no significant differences.

[leanprover-community-bot]

Mathlib CI status (docs):

• ❗ Batteries/Mathlib CI will not be attempted unless your PR branches off the nightly-with-mathlib branch. Try git rebase cf8315ed962b989f7d3b5da0a0d85fef49c460ac --onto 0a9c24649767dea857a388e5385b7ae94bfd0185. You can force Mathlib CI using the force-mathlib-ci label. (2025-06-11 08:58:37)

[Kha]

!bench

[leanprover-bot]

Here are the benchmark results for commit f0ff2a8.
There were significant changes against commit cf8315e:

  Benchmark        Metric       Change
  ===============================================
+ rbmap_10         task-clock    -1.0%  (-21.0 σ)
+ rbmap_10         wall-clock    -1.0%  (-20.3 σ)
- riscv-ast.lean   wall-clock     6.0%   (95.4 σ)
+ stdlib           blocked       -1.8%  (-46.7 σ)
+ stdlib           grind simp    -1.1% (-180.5 σ)