I'm trying to add text that sits on top of (or right below) a notehead
inside of the staff. This is possible with fingerings, but once you put the
number in quotes, or a letter in quotes, it no longer works.
What I've done so far is: disable outside-staff-priority to allow the text
to collide with the staff, and disable staff-padding to allow the text to
fall down (it would fall to the correct spot if this were fingering).
One of the main issues is that disabling outside-staff-priority allows the
text to collide with the noteheads.
\version "2.24.2"
\relative c' {
\omit Score.Stem
\override TextScript.staff-padding = #'()
\override TextScript.outside-staff-priority = ##f
c^"c"
d^"d"
}