fix logic issues in predprey example

[JostMigenda]

Discovered this issue while trying to develop more interactive exercises for the optimisation part.

Right now, prey can’t have children (the function creates them, but doesn’t return them); but if they could, those would be added to the list of predators. This PR fixes both issues, ensuring more realistic behaviour. However, the downside is that the number of prey rises near-exponentially during the first steps, significantly reducing the number of steps that we can calculate in a reasonable time to about 50-ish.

I’ll also need to check how much this affects profiling results; that’s why I’m marking it as a draft for now.

[github-actions]

Thank you!

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⏱️ Updated at 2025-11-03 07:53:10 +0000

[Robadob]

Oops thats quite the oversight, may need to fiddle with the configuration for how much food is required to reproduce etc.