feat(skill): add round end skill trigger system

新增回合结束（FEnd）类型的技能触发机制，包括：
1. 新增SkillTriggerType.FEnd枚举与相关配置映射
2. 为英雄、怪物属性组件添加回合结束技能的运行时解析与存储
3. 实现关卡节间流转时触发全队英雄回合结束技能的逻辑
4. 完善战力计算、技能图标检索等配套支持逻辑

assets/script/game/hero/Mon.ts

@@ -241,6 +241,7 @@ export class Monster extends ecs.Entity {
         model.runtime_call = resolveTriggerByLv(model.call, mon_lv);
         model.runtime_dead = resolveTriggerByLv(model.dead, mon_lv);
         model.runtime_fstart = resolveTriggerByLv(model.fstart, mon_lv);
+        model.runtime_fend = resolveTriggerByLv(model.fend, mon_lv);
         model.runtime_atking = resolveTriggerByLv(model.atking, mon_lv);
         model.runtime_atked = resolveTriggerByLv(model.atked, mon_lv);
         // 复活已纳入 dead 触发组，无需单独解析 revive