fix image loading
fix #23863: Crash when inserting a horizontal frame before an initial MM rest
fix #23799: annotations deleted with chordrests

Segment annotations are currently deleted if the last chordrest in that
segment is deleted - either because you selected a region containing
this chordrest and hit Cut/Delete or because you lengthened a previous
chordrest to subsume this one.  But the 1.3, and expected, behavior is
that annotations remain even when chordrests are deleted.
uncomment measure tests
add tests

test new behavior - lengthening note and clearing selection preserve
chord symbols
Merge pull request #589 from MarcSabatella/23799-lengthen-deletes-text

23799 annotations deleted when chordrests are
fix #23879: unlink chord symbols within score/part

Don't duplicate chord symbols between linked staves within a score/part.
Treat staff text similarly.
fix #23883: create segments for chord symbols

When adding a chord symbol to a staff in a score with a linked part,
create a new segment for the chord symbol in the linked part if
necessary.
add tests

add tests: add chord to score with linked staff, add chord to score with
linked part
also exclude figured bass, lyrics, dynamics
Allow to assign lyrics to multiple tracks
Small code formatting
Fix chords with equal onTime values (was a wrong drum voicing)
Fix multiple voices for non-drum tracks
Fix possible tuplet erasure in drum track
Fix tying of notes of intersected tuplets
Comments for tuplet selection-optimization functions
Replace const reference to int by int
Add Q_ASSERT: error when equal chords in MIDI tuplets
Add Q_ASSERT: error when no chords in a tuplet