feat: 为英雄和怪物添加下落入场动画

- 在 MissionHeroComp 和 MissionMonComp 中定义下落高度常量
- 修改英雄和怪物的加载方法，接受目标落地高度参数
- 使用 Tween 实现平滑下落动画，下落距离越大持续时间越长
- 下落期间禁用移动和碰撞器，落地后恢复
- 为怪物添加随机下落高度偏移，减轻重叠感

assets/script/game/map/MissionHeroComp.ts

@@ -13,6 +13,7 @@ const { ccclass, property } = _decorator;
 @ccclass('MissionHeroCompComp')
 @ecs.register('MissionHeroComp', false)
 export class MissionHeroCompComp extends CCComp {
+    private static readonly HERO_DROP_HEIGHT = 260
     timer:Timer=new Timer(2)
     Friend_is_dead:boolean=false
     current_hero_uuid:number=0
@@ -59,8 +60,9 @@ export class MissionHeroCompComp extends CCComp {
         let hero_pos=0
         let hero = ecs.getEntity<Hero>(Hero);
         let scale = 1
-        let pos:Vec3 = HeroPos[hero_pos].pos;
-        hero.load(pos,scale,uuid);
+        let landingPos:Vec3 = HeroPos[hero_pos].pos;
+        let spawnPos:Vec3 = v3(landingPos.x, landingPos.y + MissionHeroCompComp.HERO_DROP_HEIGHT, 0);
+        hero.load(spawnPos,scale,uuid,landingPos.y);
     }
 
 
@@ -70,4 +72,4 @@ export class MissionHeroCompComp extends CCComp {
     reset() {
         // this.node.destroy();
     }
-}
+}