Zombies and their variants have lost their special animation when holding spears

Zombie variant mobs(Zombie, Husk, Zombified Piglin, Zombie Villager) lose their spear attack animation.

Trigger:

When a zombie has not performed any attack and have a spear, its spear animation is missing.

Temporary Fix:

After the mob executes one regular non-spear-charge attack (e.g., a bare-handed hit), the spear animation returns and works correctly.

State Reset:

Exiting and re-entering the world causes the animation glitch to reappear.

Contrast:

Piglins' spear animations function normally in all scenarios and are unaffected.