This is the logic from the Robot Destruction map Asteroid, extracted and isolated so you can implement it in your own RD map. When you compile your map, you will need to generate a nav mesh for it in order for the robots to spawn and move. You can do that using the console command nav_generate.
Please note that naming any of the entities differently may cause your map to crash. I experienced crashing during the 72hr competition, and naming the entities to match those in Asteroid was the only action I took before the map worked without crashing. I think it's unlikely to be the cause but it's worth bearing in mind.
Robot Destruction is in beta, so the way these entities work might change in the future. I doubt it will break the connections between the robots, paths and logic entities in here, but you should keep an eye on it.
If you would like to know what inputs and outputs each of the entities support, you can type ent_info <entity classname> in TF2's console. Note that it's not currently possible to change the victory countdown time during the map, or the win limit, or affect a robot's health. These values are baked in. You would need a SourceMod plugin to do it.
I will update the prefab when necessary, and will delete it if RD is ever included in A Boojum Snark's Ultimate Mapping Resource Pack.