You were already doing it, with
msg.post("@render:", "use_fixed_fit_projection", { near = -1, far = 1 })
Or at least that lets you change the near and far distance, and you have a few options for what type of projection to use. See the manual for full details.
-1 or -10 don’t matter by themselves, but you will only see things that are between your projection’s near and far distances. With the default -1 to +1, you have a lot of precision close to zero. You can put things at 0.001 or 0.002 for instance.