Analyze a chess position with the Stockfish engine and return the best move.

Accepts a position as FEN or PGN (or omit it for the starting position). Returns the best move (in both UCI and human-readable SAN), the engine's evaluation, and whose turn it is. Optionally include the engine's predicted best line.

Use this whenever you need the strongest move or an evaluation for a chess position. You do NOT need to set up the position and search separately — one call does both.