petrol-fastwin-v3 (WBF ensemble)

Combines two distinct top public detectors via Weighted Boxes Fusion:

• weights/havengo.onnx — high m50 (~0.901), lower fp pillar (0.884)
• weights/superbit.onnx — sourced from SuperBitDev/petrol2, higher fp pillar (0.944)

Per-model weights 0.45 / 0.55 favor SuperBit slightly to push the ensemble toward fewer false positives. Combined latency ≈ 2.5–3 s p95 (well inside the 10 s gate).