flutter_midi_command_web unavailable in pub.dev

Hi, this looks really promising; is this plugin usable? and if so how can we depend on it?

```
> flutter pub add flutter_midi_command_web
Because <project> depends on flutter_midi_command_web any which doesn't exist (could not find package flutter_midi_command_web at https://pub.dev), version solving failed.
pub finished with exit code 65
```
