init: Unity 6 프로젝트 초기 설정

Unity 6000.4.0f1, URP 2D 프로젝트 초기 구조.
CLAUDE.md, .gitignore 포함.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Assets/NewMonoBehaviourScript.cs

@@ -0,0 +1,16 @@
+using UnityEngine;
+
+public class NewMonoBehaviourScript : MonoBehaviour
+{
+    // Start is called once before the first execution of Update after the MonoBehaviour is created
+    void Start()
+    {
+        
+    }
+
+    // Update is called once per frame
+    void Update()
+    {
+        
+    }
+}