chore: add radar-based bench suite for stdlib

[Garmelon]

This PR adds a new radar-based temci-less bench suite that replaces the stdlib benchmarks from the old suite and also measures per-module instruction counts. All other benchmarks from the old suite are unaffected.

The readme at tests/bench-radar/README.md explains in more detail how the bench suite is structured and how it works. The readmes in the benchmark subdirectories explain what each benchmark does and which metrics it collects.

All metrics except stdlib//max dynamic symbols were ported to the new suite, though most have been renamed.

[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 5cc0a103468a8da333f1f07781e5b83799582f6f --onto 5a4226f2bdcc6299df76285b1d30f238546c09fe. You can force Mathlib CI using the force-mathlib-ci label. (2025-11-19 18:46:30)
• ❗ Batteries/Mathlib CI will not be attempted unless your PR branches off the nightly-with-mathlib branch. Try git rebase 6da35eeccb726b67d9b32ab7bbd67ac00ed93589 --onto f2e191d0afbb5adcc6f12e1779c8b141fc9af996. You can force Mathlib CI using the force-mathlib-ci label. (2025-11-24 15:48:36)

[leanprover-bot]

Reference manual CI status:

• ❗ Reference manual CI will not be attempted unless your PR branches off the nightly-with-manual branch. Try git rebase 5cc0a103468a8da333f1f07781e5b83799582f6f --onto d3dda9f6d4428a906c096067ecb75e432afc4615. You can force reference manual CI using the force-manual-ci label. (2025-11-19 18:46:32)
• ❗ Reference manual CI will not be attempted unless your PR branches off the nightly-with-manual branch. Try git rebase 6da35eeccb726b67d9b32ab7bbd67ac00ed93589 --onto d3dda9f6d4428a906c096067ecb75e432afc4615. You can force reference manual CI using the force-manual-ci label. (2025-11-24 15:48:37)

[Garmelon]

I'm going to rename the stdlib benchmark to build first, then this PR should be ready.

[Garmelon]

!radar

[leanprover-radar]

Benchmark results for 2c51e9e against 6da35ee are in! @Garmelon

Runs (1)

• other exited with code 1 (🟥)

[Garmelon]

!radar

[leanprover-radar]

Benchmark results for 162edd5 against 6da35ee are in! @Garmelon