[FEATURE]: Provide an obvious way to access underlying data arrays within a Figure object (rather than the base64-encoded versions)

Hi, I have some some code here, as below (edited to remove extra logs). I'm converting a plotly figure into json, and then loading it with json loads. You would expect that to preserve the original data.

'

However, as you can see, the "y" data (which had previously been an array of large numbers) are wrongly converted into this "bdata" thing instead.

I was able to solve this and get the data in the format I wanted by going from 6.0.1 -> 5.24.1, which was the last stable build I was using. I think this is a pretty fundamental issue, so let me know if there's anything else I can share.

Figure オブジェクトの JSON 変換パスから始め、json loads を使って報告されたケースを再現し、バージョン 6.0.1 と 5.24.1 の出力を比較します。y 配列が bdata になる理由を追跡し、base64 エンコードなしで元の基盤配列にアクセスできる明確な方法を完了条件として定義します。