Cannot add arbitrary data to tooltips.

[x-tabdeveloping]

I suppose you already know about this, as it is mentioned in the documentation, but it is impossible to display arbitrary text in the tooltip upon hover (similar to Plotly). This would be a very useful feature, and it is a dealbreaker for me not to have it.

Here is a reproducible example:

import xy

data = {
    "x": [0,1,2,3],
    "y": [0,1,2,3],
    "article_title": ["this", "that", "foo", "bar"]
}

chart = xy.scatter_chart(
    xy.scatter(
        x="x", y="y", data=data,
    ),
    xy.tooltip(
        fields=["article_title"],
    ),
)

The article titles will not be shown upon hover, but rather only the "x" and "y" values.