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
fix #19306 : Elements of instruments added after creation not positioned correctly
Update libmscore/system.cpp
fix #19687 : moving bracket causes crash
Stops continuous reformatting of float data entered in inspector widgets
Undo commit from muelleki/17906-chords that conflicts with watery/17906-midichordinput
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.
Merge pull request #181 from mgavioli/Fix_#19455_entering_floats_in_inspector

#19455 - Entering float numbers in inspector
Merge pull request #183 from mgavioli/Fix_#19455_entering_floats_in_editttols

#19455 Entering float numbers in EditTools
Merge pull request #184 from mgavioli/Fix_#19809_semibreve_and_breve_vert_misalignment

Fix #19809 Semibreve and breve vertical misalignment
Merge pull request #156 from mgavioli/Fix_#19472

Fix #19472: [Left]/[Right] from more element types
create clef for all system - bugfix
fix typo and infinite loop in selectedNote()
Merge pull request #186 from AntonioBL/firstsystem

Fix #19852 : "Create clef for all systems" not working properly when unchecked
enhance 1.2 symbol import
tune layout rules to better match 1.2 behaviour
check for bad note head types