Dots with @data-related in SVG with svgHtml5 option

[wergo]

Is your feature request related to a problem? Please describe.
With the current release 4.4 and when using the svgHtml5 option, the ledger lines in the SVG have a @data-related attribute pointing to the corresponding note elements (see #3858, #3861), because they are not placed inside the note elements they are belonging to:

A similar case can be found in a dotted chord: the dots elements are located inside a <g> element that is a child to the chord element and a sibling to the individual note elements. However, there is no connection between the individual dots elements (ellipse) and their corresponding note elements. (In the case of a single note, the dots element is a child of that note, so the reference is evident.)

Describe the solution you'd like
It would be great, if the svgHtml5 option would also add @data-related attributes to the ellipse elements (at least inside chords) that each point to the @data-id of the corresponding note elements.

[lpugin]

Since the dots are given by an attribute on the chord it will be difficult to do this. Could you describe the context in which this would be useful for you?