chore: update fight logic and effect implementations

logic/service/fight/action.go

@@ -199,7 +199,6 @@ func (f *FightC) UseSkillAt(c common.PlayerI, id uint32, actorIndex, targetIndex
 		BaseAction: action.NewBaseAction(c.GetInfo().UserID),
 	}
 	ret.ActorIndex = actorIndex
-	ret.TargetIndex = targetIndex
 
 	self := f.getInputByUserID(c.GetInfo().UserID, actorIndex, false)
 	if self == nil {
@@ -225,9 +224,28 @@ func (f *FightC) UseSkillAt(c common.PlayerI, id uint32, actorIndex, targetIndex
 		}
 
 	}
+	ret.TargetIndex = normalizeSkillTargetIndex(actorIndex, targetIndex, ret.SkillEntity)
 	f.submitAction(ret)
 }
 
+func normalizeSkillTargetIndex(actorIndex, targetIndex int, skill *info.SkillEntity) int {
+	if skill == nil {
+		return targetIndex
+	}
+	// 约定：非负目标位表示敌方；负值 -(index+1) 表示同侧（自己/队友）
+	if _, targetIsOpposite := DecodeTargetIndex(targetIndex); !targetIsOpposite {
+		return targetIndex
+	}
+	// GBTL.AtkType: 0=所有人 1=仅己方 2=仅对方 3=仅自己（默认2）
+	switch skill.XML.AtkType {
+	case 1, 3:
+		// 旧协议未传目标时，己方类技能默认作用自己；新协议可通过负编码显式指定队友。
+		return EncodeTargetIndex(actorIndex, false)
+	default:
+		return targetIndex
+	}
+}
+
 // 玩家使用技能
 func (f *FightC) Capture(c common.PlayerI, id uint32) {
 	if f.closefight {