修复了重型防空炮不能索敌的bug；
几款重型防空炮将使用独特的目标选择器aa_heavy.inc优先打击飞机和坦克；
降低了掩体的防护收益；
美军82师（晚期）的皮肤错误修复；
为减少ai与玩家交火后一直保持开火状态不移动并且与其他小队聚成一团，降低了人类对sort threat的优先级.

Fixed the bug where heavy anti-aircraft guns could not target enemies;
Several heavy anti-aircraft guns will use the unique target selector aa_heavy.inc to prioritize attacking aircraft and tank；
Reduced the defensive benefits of cover;
Corrected the skin error for the US 82nd Division (late stage)；
To reduce the issue where AI, after engaging players, continues firing without moving and clusters together with other squads, the priority of humans in the **sort threat** calculation has been lowered.

anm file fix

移动动画；小队系统；smg平衡

***为德军征服模式添加了两种新的机械化工兵小队:
1.搭乘sdkfz7的工兵小队(中期)，
2.搭乘sdkfz7的工兵小队(晚期)。
后续更新会为各主要国加添加更多类型的步兵小队。

*** has added two new mechanized engineer squads to the German conquest mode:
Engineer squad mounted on Sd.Kfz. 7 (mid-phase),
Engineer squad mounted on Sd.Kfz. 7 (late-phase).
Future updates will introduce more types of infantry squads for each major faction.