Add hidden_states.34 output (folded-carry seed) for the #1716 speculative contract

Ship faithful onnx-genai v1 inference_metadata.yaml (validated vs #1716 schema); preserve mobius emitter output as .mobius.yaml; add reference + generator

Publish metadata-complete Gemma-4 E2B-it text decoder (fp16 CUDA): canonical inference_metadata.yaml + policies + L4/L5 parity; supersedes prior metadata-less multimodal export