Best-of-N
Give the LLM N valid attempts at the same parent before committing to the global best, then repeat.
"""Best-of-N Memory component — none.
Best-of-N keeps no cross-candidate free-form knowledge; the plain loop leaves Memory empty (NullMemory).
"""
from __future__ import annotations
from ...components.memory import NullMemory
BestOfNMemory = NullMemory