Feature request: Prefatory bars/incipit

[iainhallam]

When transcribed into a modern notation, pieces of early music often include a short passage (sometimes a single note, sometimes the first phrase) in the original clefs, keys, time signatures, and notation styles.

This request is for incipit at the start of the score or start of a section.

[iainhallam]

Following on from @jonarnoldmusic in #15732 (comment), key features would include:

• Automatic width, simpler creation than current process
• No system bracket to the left
• Clefs, key signatures, time signatures/mensuration signs that may be different or the same as the music that follows
• Standard entry of notes in the incipit
• Ambitus at the clef in the incipit reflecting the range in that part but adjusted to the clef
• Ability to ignore the incipit for playback
• Making incipit staves for some parts invisible - for instance for a piano reduction alongside vocal parts

While eventually it would be great to be able to do full mensural or plainchant notation in MuseScore, I suggest that the features to enable that like appropriate clefs, keys, note styles, etc., are left to other feature requests to make this one simpler.

Another use of incpit: pitches for timpani (https://www.scoringnotes.com/news/introducing-ambitus-a-new-font-for-pitch-incipits/)