feat: VFX 인프라 구축 및 Ground Target 시스템 구현

- VfxEffect 스킬 이펙트 클래스 추가 (일회성 VFX 스폰, 위치/스케일/파티클 제어)
- SkillEffect.IsVisualOnly 프로퍼티 추가로 서버 가드 없이 모든 클라이언트에서 VFX 로컬 실행
- SkillProjectile 트레일 VFX 지원 (OnNetworkSpawn에서 양쪽 생성, despawn 시 월드 분리)
- SkillProjectile HitEffectClientRpc 추가로 충돌 이펙트 클라이언트 동기화
- Ground Target 시스템: 타겟팅 모드 상태머신, 인디케이터, 지면 위치 RPC 전달
- 마법 오름 Ground Target 스킬 에셋 및 VfxEffect 에셋 추가
- 마법 오름 애니메이션 클립 추가
- Ground layer (Layer 7) 추가
- ProjectileBasic에 trailPrefab/hitEffect 필드 추가
- Prefabs/VFX/ 폴더 생성

Assets/_Game/Prefabs/Player/Prefab_Player_Default.prefab

@@ -5059,35 +5059,35 @@ MonoBehaviour:
   ShowTopMostFoldoutHeaderGroup: 1
   skillRegistry: {fileID: 11400000, guid: 1899abd2213d1374dac386c5c865eb16, type: 2}
   skillSlots:
-  - {fileID: 11400000, guid: b7f09e0e899c8fc4bb2cc9204cc6eb4a, type: 2}
-  - {fileID: 11400000, guid: b8c86399865e91144a3d6fcfddc04fd9, type: 2}
-  - {fileID: 11400000, guid: 1020083ab98b8214f918fa2ab7c1a3a1, type: 2}
-  - {fileID: 11400000, guid: a822c7e8c7cee5546ad594b582208e53, type: 2}
-  - {fileID: 11400000, guid: 29e1ce0656471b54f84b18a773032a99, type: 2}
-  - {fileID: 11400000, guid: 2ed15dca92a165046b6df17b28f64874, type: 2}
+  - {fileID: 0}
+  - {fileID: 0}
+  - {fileID: 11400000, guid: 2b3c4d5e6f7890abcdef1234567890ab, type: 2}
+  - {fileID: 11400000, guid: a8f2a6b7c9d0e1f3a4b5c6d7e8a9f0b1, type: 2}
+  - {fileID: 0}
+  - {fileID: 0}
   - {fileID: 11400000, guid: 2ed15dca92a165046b6df17b28f64874, type: 2}
   skillLoadoutEntries:
-  - baseSkill: {fileID: 11400000, guid: b7f09e0e899c8fc4bb2cc9204cc6eb4a, type: 2}
+  - baseSkill: {fileID: 0}
     socketedGems:
     - {fileID: 0}
     - {fileID: 0}
-  - baseSkill: {fileID: 11400000, guid: b8c86399865e91144a3d6fcfddc04fd9, type: 2}
+  - baseSkill: {fileID: 0}
     socketedGems:
     - {fileID: 0}
     - {fileID: 0}
-  - baseSkill: {fileID: 11400000, guid: 1020083ab98b8214f918fa2ab7c1a3a1, type: 2}
+  - baseSkill: {fileID: 11400000, guid: 2b3c4d5e6f7890abcdef1234567890ab, type: 2}
     socketedGems:
     - {fileID: 0}
     - {fileID: 0}
-  - baseSkill: {fileID: 11400000, guid: a822c7e8c7cee5546ad594b582208e53, type: 2}
+  - baseSkill: {fileID: 11400000, guid: a8f2a6b7c9d0e1f3a4b5c6d7e8a9f0b1, type: 2}
     socketedGems:
     - {fileID: 0}
     - {fileID: 0}
-  - baseSkill: {fileID: 11400000, guid: 29e1ce0656471b54f84b18a773032a99, type: 2}
+  - baseSkill: {fileID: 0}
     socketedGems:
     - {fileID: 0}
     - {fileID: 0}
-  - baseSkill: {fileID: 11400000, guid: 2ed15dca92a165046b6df17b28f64874, type: 2}
+  - baseSkill: {fileID: 0}
     socketedGems:
     - {fileID: 0}
     - {fileID: 0}
@@ -5107,6 +5107,11 @@ MonoBehaviour:
   lineOfSightBlockLayers:
     serializedVersion: 2
     m_Bits: 0
+  groundTargetLayers:
+    serializedVersion: 2
+    m_Bits: 128
+  groundTargetMaxRange: 20
+  groundTargetIndicator: {fileID: 0}
 --- !u!114 &1242716222252539497
 MonoBehaviour:
   m_ObjectHideFlags: 0
@@ -5179,7 +5184,7 @@ MonoBehaviour:
   backName: Spine
   hipName: Hip
   twoHandedName: prop_r
-  startingWeapon: {fileID: 11400000, guid: 646964ccbda84e947b97537d7f7813aa, type: 2}
+  startingWeapon: {fileID: 11400000, guid: 73962a4faafaf144c85cd6fbd5208eee, type: 2}
   startingOffhandWeapon: {fileID: 0}
   registeredWeapons:
   - {fileID: 11400000, guid: 646964ccbda84e947b97537d7f7813aa, type: 2}

Assets/_Game/Prefabs/Skills/Prefab_Skill_ProjectileBasic.prefab

@@ -17,7 +17,7 @@ GameObject:
   - component: {fileID: 7983858810247897309}
   - component: {fileID: 238577235165339599}
   m_Layer: 0
-  m_Name: Projectile_Basic
+  m_Name: Prefab_Skill_ProjectileBasic
   m_TagString: Untagged
   m_Icon: {fileID: 0}
   m_NavMeshLayer: 0
@@ -128,7 +128,7 @@ MonoBehaviour:
   m_Script: {fileID: 11500000, guid: d5a57f767e5e46a458fc5d3c628d0cbb, type: 3}
   m_Name: 
   m_EditorClassIdentifier: Unity.Netcode.Runtime::Unity.Netcode.NetworkObject
-  GlobalObjectIdHash: 897395779
+  GlobalObjectIdHash: 1397402255
   InScenePlacedSourceGlobalObjectIdHash: 0
   DeferredDespawnTick: 0
   Ownership: 1
@@ -231,5 +231,7 @@ MonoBehaviour:
   lifetime: 5
   penetrate: 0
   maxPenetration: 1
-  hitEffect: {fileID: 0}
+  hitEffect: {fileID: 1876479836436568, guid: fe8a785dacf0f634da597527ea1b09a6, type: 3}
   hitEffectDuration: 2
+  trailPrefab: {fileID: 1027031658262514, guid: add4c8cecb195fd4c89195f49353ebc9, type: 3}
+  trailDuration: 0.3

Assets/_Game/Prefabs/VFX.meta

@@ -0,0 +1,8 @@
+fileFormatVersion: 2
+guid: 50eac4dcb8da52641bc316924c02fb75
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: