Let Homemade Engines Communicate via Chat

[Others]

Unless I'm missing something, it's not currently possible to have a homemade engine read or write chat messages during games. (At least not without hacking around current abstractions.)

When developing my bot, it would be super helpful to be able to write a diagnostic message into chat in some exceptional situations. So I'm primarily interested in being able to type unilaterally during the "search" call.

I think I can probably accomplish what I want by just hacking on the code a little bit myself, but I'm wondering if it would be in scope for this to be properly supported by the project.