Phase 10.8: torchao/bnb quant sweep on iter1-independent. bf16 already
optimal; torchao int8-wo gives -19% VRAM at no F1 cost; all 4-bit
variants collapse (ModernBERT-large too quant-sensitive).
Phase 10.9: ONNX export + ORT eval. Legacy exporter only working path
(dynamo adds 56 Memcpy nodes); ORT fp32 -22% latency vs torch via
kernel fusion but bf16+flash-attn-2 still wins; fp16 broken on rotary;
dynamic int8 silently CPU-fallback + 0.5 F1 collapse.
Driver scripts wired to bun run py:quant / py:onnx; full reports at
results/eval/{quant,onnx}/REPORT.md.
