```

feat(materials): 删除TowerEnemy和TowerPlayer材质文件

移除项目中不再需要的TowerEnemy.mat和TowerPlayer.mat材质文件，
以及对应的.meta元数据文件。这些材质文件已通过其他方式重构或不再使用。
```

Assets/Shader/Outline.shader

@@ -0,0 +1,54 @@
+Shader "Unlit/Outline"
+{
+    Properties
+    {
+        _OutlineColor ("描边颜色", Color) = (0,0,0,1)
+        _OutlineWidth ("描边宽度", Range(0.001, 0.1)) = 0.015
+    }
+    SubShader
+    {
+        Tags { "RenderType"="Opaque" "Queue"="Geometry+10" }
+        LOD 100
+
+        Pass
+        {
+            Cull Front
+            ZWrite On
+
+            CGPROGRAM
+            #pragma vertex vert
+            #pragma fragment frag
+            #include "UnityCG.cginc"
+
+            struct appdata
+            {
+                float4 vertex : POSITION;
+                float3 normal : NORMAL;
+            };
+
+            struct v2f
+            {
+                float4 pos : SV_POSITION;
+            };
+
+            fixed4 _OutlineColor;
+            float _OutlineWidth;
+
+            v2f vert (appdata v)
+            {
+                v2f o;
+                // 沿法线方向外扩顶点
+                float3 expandedPos = v.vertex.xyz + v.normal * _OutlineWidth;
+                o.pos = UnityObjectToClipPos(float4(expandedPos, 1.0));
+                return o;
+            }
+
+            fixed4 frag (v2f i) : SV_Target
+            {
+                return _OutlineColor;
+            }
+            ENDCG
+        }
+    }
+    FallBack "Unlit/Texture"
+}

Assets/Shader/Outline.shader.meta

@@ -0,0 +1,9 @@
+fileFormatVersion: 2
+guid: CSlN43+rUHgAdI/KyDPCnVd69qNd81nKHAi7hla8XbgevFI9DqsU9m0=
+ShaderImporter:
+  externalObjects: {}
+  defaultTextures: []
+  nonModifiableTextures: []
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: