[NPCs] Xen grenade-spawned Stukabats stuck in divebomb anim and explode, lose track of player after first attack

[cuttrogue]

Describe the bug

When spawned with Xen grenades Stukabats perform divebomb animation continuously and then explode if not engaged. When engaged they lose track of player after first attack.

Important: Only happens when spawned with Xen grenades. When spawned with npc_create they behave properly.

Steps to reproduce

Steps to reproduce the behavior:

1. Spawn a stukabat with a Xen grenade..
2. Try engaging it and let it attack you, move out of its attack.
3. See how it loses track of player once you get behind it after it attacks.

Expected behavior

In 1.6.0 stukabats stay in air without continuously performing divebomb animation then continuously keep attacking player until death of either, without losing track of player.

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Additional context

1. video demonstrating a stukabat going up and down repeatedly in one place without noticing the player, then exploding
2. Video demonstrating a stukabat losing track of player after first attack, then exploding
3. Video demonstrating a stukabat continuously attacking the player without losing track in 1.6.0 version