Breaking 0.669 to Reach Top 5 in Kaggle's "Name That LLM": The Decoy Trap, Dual-SVC & Sequence Encoders

How we de-camouflaged public SOTA notebooks, added DeBERTa-v3 sequence classification, recalibrated soft Sinkhorn balancing, and applied deterministic typography invariants to push beyond 0.672 into Top 5.