Attack bug: Crashing airplane causes next queue item to be skipped

If you have a fighter with an attack queue on 3 airplanes, e.g. A,B,C.

If target A is crashing, the fighter doesn't shoot anything. Once A is dead, the attack command for B is removed from the queue and the fighter attacks C.

https://github.com/user-attachments/assets/6b611c67-aa55-4c46-90c2-c07c13678668

B should not be skipped by the engine.

Reproduce the reported attack queue scenario with a fighter targeting crashing airplanes A, B, and C, then trace the attack-queue handling when A dies. Done means the fighter attacks B next rather than removing B and proceeding to C; add or run a regression test if the relevant test entry point is found.

Written by the indexing model from the issue text.