Add InputDeviceIconSetSO configuration guide and related documentation

- Created a new markdown file detailing the configuration of InputDeviceIconSetSO.
- Included sections on system architecture, field explanations, image specifications, and complete workflow from setup to runtime.
- Documented the automatic device recognition logic and provided troubleshooting for common issues.
- Added references to relevant files and scripts for easier navigation.

Assets/_Game/Scripts/UI/InputDeviceIconSetSO.cs

@@ -13,18 +13,27 @@ namespace BaseGames.UI
         [System.Serializable]
         public struct IconEntry
         {
-            public string  BindingPath;  // InputSystem binding path，e.g. "<Keyboard>/space"
-            public Sprite  Icon;
+            [Tooltip("InputSystem 绑定路径，如 <Keyboard>/space 或 <Gamepad>/buttonSouth。改键后路径变化，图标集中须包含全部可能按键的映射。")]
+            public string BindingPath;
+            public Sprite Icon;
         }
 
+        [Tooltip("标识此图标集对应的输入设备类型（仅作编辑器说明，运行时由 InputIconService 选择）")]
+        [SerializeField] private InputDeviceType _deviceType;
+
         [SerializeField] private IconEntry[] _entries;
 
+        /// <summary>此图标集对应的设备类型。</summary>
+        public InputDeviceType DeviceType => _deviceType;
+
         /// <summary>根据 binding path 查找对应图标；未找到返回 null。</summary>
         public Sprite GetIcon(string bindingPath)
         {
-            if (_entries == null) return null;
+            if (_entries == null || string.IsNullOrEmpty(bindingPath)) return null;
+            // 先精确匹配，再做路径前缀不区分大小写匹配（兼容大小写差异）
             foreach (var entry in _entries)
-                if (entry.BindingPath == bindingPath) return entry.Icon;
+                if (string.Equals(entry.BindingPath, bindingPath, System.StringComparison.OrdinalIgnoreCase))
+                    return entry.Icon;
             return null;
         }
     }