fix(BT12-Dev-Clone δ): Tests/Editor asmdef 삭제 → default Assembly-CSharp-Editor 흡수

CS0234 EerieVillage.Skills.Effectors namespace 부재 근본 fix:
- 원인: asmdef autoReferenced=true 영역도 main Assembly-CSharp 영역 reference X (asmdef 메커니즘 영역 default assembly 영역 격리)
- 본 PM 자성 #3 누적 (C39-10 위반·asmdef 영역 사전 동작 영역 추정)
- fix: asmdef + .meta 삭제 → Tests/Editor 영역 default Assembly-CSharp-Editor 영역 자동 흡수 → main Assembly-CSharp (CloneInstance·PlayerSkillInventory 등) 자동 reference
- NUnit: default Editor assembly 영역 Unity Test Framework 자동 reference 영역 (UNITY_INCLUDE_TESTS 영역 정합)

PD Editor Refresh 시 Test Runner CloneSkillTests 7건 자동 인식 영역 (default Assembly-CSharp-Editor 영역 NUnit 영역 정합)

Assets/Tests/Editor/EerieVillage.Tests.Editor.asmdef

@@ -1,21 +0,0 @@
-{
-    "name": "EerieVillage.Tests.Editor",
-    "rootNamespace": "",
-    "references": [
-        "UnityEngine.TestRunner",
-        "UnityEditor.TestRunner"
-    ],
-    "includePlatforms": [
-        "Editor"
-    ],
-    "excludePlatforms": [],
-    "allowUnsafeCode": false,
-    "overrideReferences": false,
-    "precompiledReferences": [],
-    "autoReferenced": true,
-    "defineConstraints": [
-        "UNITY_INCLUDE_TESTS"
-    ],
-    "versionDefines": [],
-    "noEngineReferences": false
-}

Assets/Tests/Editor/EerieVillage.Tests.Editor.asmdef.meta

@@ -1,7 +0,0 @@
-fileFormatVersion: 2
-guid: 4e0b3a471538c044b8615276aaa65ba0
-AssemblyDefinitionImporter:
-  externalObjects: {}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: