Grouping grobs

[lilypond]

Hi,

I'm new to Lilypond and am trying to generate SVG output for use elsewhere. In 
general I'd like to create fragments of music and add ids to each group. So far 
I've seen that each grob is output as its own <g>--is there a way to group at a 
higher level, say markup, staff, etc.?

John\version "2.22.2"
\markup {
% with SVG output this is two <g>: notehead and dot
% \overrideNoteHead.output-attributes.id= 123
\note {4.} #0
}