Optimizations

I feel like there could be some optimizations concerning the image update.

1. We should draw binary data directly on the canvas using:

context.putImageData(binary_data);

instead of creating a Blob that is png encoded. That would also allow the back-end to not waste time encoding into png (if that is possible).

2. I feel like the "diff" computation should actually be slower than sending the full image, as it needs an extra computation of "which pixels actually needs a redraw?": https://github.com/matplotlib/matplotlib/blob/5fc44eea64a57ab1c6d236cf7c71906c9d40e6f6/lib/matplotlib/backends/backend_webagg_core.py#L190-L195.
   Plus, we are still sending a full image. Maybe the png encoding does some compression if lots of pixels are transparent? If that is not the case, we are still sending the same amount of data.

参照されている matplotlib/backends/backend_webagg_core.py の画像更新コードから始め、ipympl における対応する canvas 更新のエントリーポイントを追跡してください。提案されているバイナリデータのパスを現在の PNG パスおよび diff パスと比較し、いずれか一方を変更する前にベンチマークと受け入れ基準を定義してください。