ConstDrop the notes that never sound.
A MIDI or DAW import routinely carries zero-length artefacts. Every entry point in this library ignores them, but a caller holding such an array still has to decide what to do with it before comparing note counts or indices; this is the one filter to apply.
The note events to filter.
A new array containing only the notes with a positive duration.
Alias that makes the shared positive-duration policy explicit at API entrances.