Allow the tooltip to remain open on hover

### Feature Proposal

Hi there,

I've got a slight issue with what I'm trying to achieve...

I'd like to be able to hover on my tooltip, but as soon as I move my cursor over the tooltip it disappears
https://github.com/user-attachments/assets/5c0056f3-c6c7-4a3c-b733-dbbe744e86f4

I've tried playing with a few of the [interaction modes](https://www.chartjs.org/docs/latest/samples/tooltip/interactions.html) but none quite do what I want, it's particularly problematic with a scatterplot.

### Possible Implementation

I think ideally what I'm looking for is that the interaction covers the point and the resulting tooltip area, perhaps something like
````
interaction: {
intersect: true,
mode: 'point+tooltip',
},
````

It might be that this is best catered for by a [custom interaction mode](https://www.chartjs.org/docs/latest/configuration/interactions.html#custom-interaction-modes) but I thought I'd flag it for feature consideration.