I thought you were hosting a multiplayer server with other people so I thought you could just make it a rule and ban people who used it, since you didn't specify bots. But yeah, bots arent coded to abide by the server rules, at least not the disallow ranged rule. Sadly, I couldn't find any mods that can circumvent this, for now I guess your only option is to use shields.
I doubt devs would fix that option to include bots since the game is so old and all the developer time is being spent on the new game. And yeah, because of the same reason there aren't many people visiting the forums either.