Minimax leaf nodes now return a positional score instead of 0, using
playable-threat detection (±100), non-playable threats (±40), fork
bonus (±200), two-in-a-row (±5), and center control (±3). Phase 1
is split into two passes so the AI never blocks when it can win.
Game sequence is now auto-logged to the browser console on game end.
Applied to all three implementations (C++, JS, Python).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>