Enhancement: Midi Out Plugin

Nobody has claimed this yet.

It would be neat to have a dedicated midi out instrument that's only function is to send midi to instruments in LMMS listening on whatever midi channel it is set to.

As I've read it is possible to use an empty ATP to send midi out, but there is no way to bridge that to instruments inside LMMS without using external programs/devices (which in turn breaks the project if they are configured exactly the same each time the project is opened, which is a pain).

Uses of this would be to use one instrument to trigger many layered things, using midi to control parameters in VST effects that can't be controlled with LMMS's automation, and possibly, once implemented, have a role in exporting midi. There are probably more uses to this but eh. I just want a way to bounce midi around inside LMMS, which currently can't be done within the program to my knowledge.

The issue names no files, tests, or entry points. Start by tracing how LMMS currently routes MIDI between instruments and how instrument channels are represented. Done means a dedicated MIDI-out instrument can send MIDI to other instruments inside LMMS without external devices, with behavior suitable for the requested layering and parameter-control uses.

Written by the indexing model from the issue text.