fix #24349: fret offset text size as style
fix #24349: fret offset text left/right, as style
fix #24494: distance staff to fretboard diagram
minor fixes to the previous 2 commits

minor, as it works without those, but seems cleaner with:
ST_fretNumPos is int -> styleI() rather than stylD()
ST_staffFretDist gets multiplied by _spatium -> styleP() does this for
us, styleD() does not.
UI improvements
making fretboard distcance to staff consistent

with other similar settings by using negative values if above staff
fix chord symbol to fretboard diagram distance
Merge pull request #684 from Jojo-Schmitz/fretboard

Fretboard Diagrams: adding/fixing style settings