chore: Assets 디렉토리 구조 정리 및 네이밍 컨벤션 적용

- Assets/_Game/ 하위로 게임 에셋 통합
- External/ 패키지 벤더별 분류 (Synty, Animations, UI)
- 에셋 네이밍 컨벤션 확립 및 적용
  (Data_Skill_, Data_SkillEffect_, Prefab_, Anim_, Model_, BT_ 등)
- pre-commit hook으로 네이밍 컨벤션 자동 검사 추가
- RESTRUCTURE_CHECKLIST.md 작성

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Assets/External/Models/SidekickCharacters/Scripts/Runtime/Utils/PartGroupUtils.cs

@@ -0,0 +1,89 @@
+// Copyright (c) 2024 Synty Studios Limited. All rights reserved.
+//
+// Use of this software is subject to the terms and conditions of the Synty Studios End User Licence Agreement (EULA)
+// available at: https://syntystore.com/pages/end-user-licence-agreement
+//
+// For additional details, see the LICENSE.MD file bundled with this software.
+
+using Synty.SidekickCharacters.Enums;
+using System;
+using System.Collections.Generic;
+
+namespace Synty.SidekickCharacters.Utils
+{
+    /// <summary>
+    ///     A collection of utility methods related to operations on PartGroup enum values.
+    /// </summary>
+    public static class PartGroupUtils
+    {
+        /// <summary>
+        ///     Get the part types that the given part group contains
+        /// </summary>
+        /// <param name="basePartGroup">The part group to get the types of</param>
+        /// <returns>A List of part types that belongs to this PartGroup</returns>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown if the part group is unrecognised</exception>
+        public static List<CharacterPartType> GetPartTypes(this PartGroup basePartGroup)
+        {
+            switch (basePartGroup)
+            {
+                case PartGroup.Head:
+                    return new List<CharacterPartType>
+                    {
+                        CharacterPartType.Head,
+                        CharacterPartType.Hair,
+                        CharacterPartType.EyebrowLeft,
+                        CharacterPartType.EyebrowRight,
+                        CharacterPartType.EyeLeft,
+                        CharacterPartType.EyeRight,
+                        CharacterPartType.EarLeft,
+                        CharacterPartType.EarRight,
+                        CharacterPartType.FacialHair,
+                        CharacterPartType.AttachmentHead,
+                        CharacterPartType.AttachmentFace,
+                        CharacterPartType.Nose,
+                        CharacterPartType.Teeth,
+                        CharacterPartType.Tongue,
+                    };
+
+                case PartGroup.UpperBody:
+                    return new List<CharacterPartType>
+                    {
+                        CharacterPartType.Torso,
+                        CharacterPartType.ArmUpperLeft,
+                        CharacterPartType.ArmUpperRight,
+                        CharacterPartType.ArmLowerLeft,
+                        CharacterPartType.ArmLowerRight,
+                        CharacterPartType.HandLeft,
+                        CharacterPartType.HandRight,
+                        CharacterPartType.AttachmentBack,
+                        CharacterPartType.AttachmentShoulderLeft,
+                        CharacterPartType.AttachmentShoulderRight,
+                        CharacterPartType.AttachmentElbowLeft,
+                        CharacterPartType.AttachmentElbowRight,
+                        CharacterPartType.Wrap,
+                        // CharacterPartType.AttachmentHandLeft,
+                        // CharacterPartType.AttachmentHandRight,
+                    };
+
+                case PartGroup.LowerBody:
+                    return new List<CharacterPartType>
+                    {
+                        CharacterPartType.Hips,
+                        CharacterPartType.LegLeft,
+                        CharacterPartType.LegRight,
+                        CharacterPartType.FootLeft,
+                        CharacterPartType.FootRight,
+                        CharacterPartType.AttachmentHipsFront,
+                        CharacterPartType.AttachmentHipsBack,
+                        CharacterPartType.AttachmentHipsLeft,
+                        CharacterPartType.AttachmentHipsRight,
+                        CharacterPartType.AttachmentKneeLeft,
+                        CharacterPartType.AttachmentKneeRight,
+                    };
+
+                default:
+                    throw new ArgumentOutOfRangeException(nameof(basePartGroup), basePartGroup, null);
+            }
+        }
+    }
+}