feat: add `FFTBatch` benchmark

[batzor]

Description

This PR adds FFTBatch benchmark of Tachyon and Plonky3.

[chokobole]

docs(bench): introduce FFTBatch benchmark should be typed with test

[chokobole]

I think

• feat(benchmark): introduce Config and Vendor and feat(benchmark): introduce FieldType for specifying which field to use should be typed with refac.

[chokobole]

• refac(benchmark): add benchmark namespace to all you can squash these change to the previous ones. Then we don't need to review this additional commits.
• style(benchmark): change integer types for consistency should be typed to refac.