doublecheck coproc and execer check

[abathur]

I noticed that lilgitd gets flagged as an execer, but the resholve derivation for lilgit itself doesn't require a lore override for it. I'm not sure if it's correct or not, but this at least suggests that execer status isn't checked for coproc.

If the executable argument to coproc can't itself have any arguments (just the executable) then this would be correct behavior. If they can have arguments, then this needs a fix.