Feature Request: I would like a CLI Option to Transpose MSCZ Files

Currently, the MuseScore 4 command-line interface does not provide a straightforward way to transpose a .mscz file by a specified interval and directly export the transposed result to a desired file format (like SVG, PDF, MusicXML, MIDI, or even a new MSCZ).

The -o / --export-to option allows exporting to various formats but operates on the original score file without applying transposition first.

The --score-transpose option does transpose, however, it only outputs the transposed score data as a JSON structure to stdout, not as a rendered file format (like SVG/PDF) or a standard score file format (like MSCZ or MusicXML) that could be used in a subsequent processing. This is quite inconvenient.

Ideally, this transposition should work seamlessly with all export formats supported by the -o option (SVG, PDF, PNG, MSCZ, MSCX, MusicXML, MXL, MIDI, WAV, MP3, FLAC, OGG), but a pure MSCZ transposition would be absolutely fine.

This feature would really come in handy for users who want to automate score processing tasks via scripting or integrate MuseScore's capabilities into other applications or workflows (like me).

Thank you for considering this feature.