Fix a little bug

Optimize the AI recruitment of newly added elephant units to make AI more inclined to recruit

Major Update
Theme: Elephants
Setting: Melee Elephants gain chariot mechanism (Melee Elephants will be invincible against melee infantry and cavalry, but are easily disrupted and killed by ranged units); the number of ranged elephant units increases to 48.
Model: The tower on top of the melee elephant is removed, and the elephant armor model is optimized. From T1 to T3, there are three types of armor.
Campaign: Maintenance cost changes to 2500/1800. In areas with blacksmiths on your side, the maintenance cost is significantly reduced; recruitment cost of camels and elephants *2, recruitment cost /2 in areas with the above habitats.
Morale: The base morale of melee elephants is reduced. Now elephants are prone to going berserk, so be careful to control them.
Ammunition: Ranged elephant ammunition is adjusted by dividing by 4.
New Units: New Zagwe Elephant Guard unit, new Gur T2 melee elephant, new Trabzon Greek Fire Elephant.

Fixed some bug

Fix a BUG where a unit's horse disappears

Fixed a BUG where Unbreakable ability prevented some units from being killed