Fix #19472

Implements [Left] / [Right] not only from notes/chord-rests but from any element whose parent is a note, a chord-rest or a segment
For elements attached to segments, move to the chord/rest in element track, if it exists
Stops continuous reformatting of float data entered in inspector widgets
Stops continuous reformatting of float data entered in EditTools widgets.
Corrects vertical alignment for stemless notes (semibreves and breves).
First commit too simplistic and didn't work for ledger lines.

Error was in determining stem X pos. Improved.