ONNX to Tensorflow.js conversion of GPT-2

[christinakopi]

Roadmap:

• ensure bijection between onnx and tfjs weights
• add progress indicator to hellaswag benchmark
• move filesystem logic to discojs-node and cli
• automate downloading onnx model from hub
• convert python script to nodejs and web-compatible logic
• experiment with webgpu for hellaswag
• experiment with converting tfjs back to onnx

The table below shows the accuracy along with the time of the evaluation on the whole HellaSwag for each model tested:

Model	Accuracy	Eval Time (s)
TFJS GPT (gpt-nano)	24.67%	1390.25
Xenova GPT-2 (ONNX)	29.03%	22767.03
Loaded TFJS GPT (from ONNX)	28.41%	12523.59

[martinjaggi]

amazing work, thanks a lot!
later i'd be very curious to check if also the conversion in the reverse direction (to onnx) works fine.

[tharvik]

haa, that's great work, well done in hacking around the onnx protobuf!
nothing blocking (except the tsc --build thing), only a few nitpicks and questions here and there