Feature request: --cpu-affinity flag to pin benchmark subprocesses to specific CPUs

Feature request: --cpu-affinity flag to pin benchmark subprocesses to specific CPUs: a task in LegoFlow-SWE (Harbor dataset). The option should support the following specification formats: - a single core number, e.g. 0 - a comma-separated list, e.g. 0,1,2 - a range, e.g. 0-3