Colored Notes for Scale Specific Instruments

Your idea

For the harp, Musescore colors notes red that are not playable with a certain pedal setting. I suggest that this feature would be applied for instruments that only play a specific scale. For example, a guzheng is tuned to the D major pentatonic scale, and cannot play F, G, C#, etc. These notes would be colored red.
The koto is tuned to the hirajoshi scale, though this scale is not fully standardized. Guzheng would probably be the only instrument this feature could be implemented for right now, but nevertheless it will be much appreciated.

Problem to be solved

(Aside from the fact that no guzheng exists currently; see issue #26054) Musescore does not notify the user when they notate impossible notes on guzheng or similar instruments.

Prior art

For the harp, Musescore colors notes red that are not playable with a certain pedal setting (that is, an alternate scale).

Additional context

No response

Checklist

• This request follows the guidelines for reporting issues
• I have verified that this feature request has not been logged before, by searching the issue tracker for similar requests

Start by reviewing issue #26054, which tracks adding the guzheng, and compare the requested behavior with MuseScore's existing harp pedal note coloring. Define how the guzheng's D-major pentatonic constraints and similar scale-specific instruments should be represented, then verify that impossible notes are visibly identified in notation.