AI not accounting for heat cost when rollup occurs

From Harkonnen in closed-3437 on RT discord:

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It looks like that evalution identical weapons as one has a nasty side effect - if firing all of them causes overheat CG does not evalute the possibility of firing obly some of them
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Start by locating the AI weapon-evaluation code that groups identical weapons during a firing decision, then reproduce the overheat case described in the issue. Check whether the evaluation considers firing only a subset of the grouped weapons; done means the AI evaluates that possibility and tests cover the reported behavior.

Written by the indexing model from the issue text.