test: 스킬 서비스 테스트 업데이트

- import 경로 변경 반영

test/core/engine/skill_service_test.dart

@@ -548,7 +548,7 @@ void main() {
         final rng = DeterministicRandom(42);
         final service = SkillService(rng: rng);
 
-        const skill = SkillData.debugMode; // ATK +25% 버프, mpCost: 100
+        const skill = SkillData.debugMode; // ATK +15% 버프, mpCost: 140
         final player = CombatStats.empty().copyWith(mpMax: 200, mpCurrent: 150);
         final skillSystem = SkillSystemState.empty().copyWith(elapsedMs: 5000);
 
@@ -560,9 +560,9 @@ void main() {
 
         expect(result.result.success, isTrue);
         expect(result.result.appliedBuff, isNotNull);
-        expect(result.result.appliedBuff!.effect.atkModifier, equals(0.25));
+        expect(result.result.appliedBuff!.effect.atkModifier, equals(0.15));
         expect(result.updatedSkillSystem.activeBuffs.length, equals(1));
-        expect(result.updatedPlayer.mpCurrent, equals(50)); // 150 - 100
+        expect(result.updatedPlayer.mpCurrent, equals(10)); // 150 - 140
       });
 
       test('중복 버프 제거 후 새 버프 적용', () {