경로 선택 탐색기 팝업 기능 구현

- StandaloneFileBrowser 에셋을 활용한 방법
- dll을 활용한 방법
- 유니티 에디터 자체 기능을 활용한 방

Assets/StandaloneFileBrowser/IStandaloneFileBrowser.cs

@@ -0,0 +1,13 @@
+using System;
+
+namespace SFB {
+    public interface IStandaloneFileBrowser {
+        string[] OpenFilePanel(string title, string directory, ExtensionFilter[] extensions, bool multiselect);
+        string[] OpenFolderPanel(string title, string directory, bool multiselect);
+        string SaveFilePanel(string title, string directory, string defaultName, ExtensionFilter[] extensions);
+
+        void OpenFilePanelAsync(string title, string directory, ExtensionFilter[] extensions, bool multiselect, Action<string[]> cb);
+        void OpenFolderPanelAsync(string title, string directory, bool multiselect, Action<string[]> cb);
+        void SaveFilePanelAsync(string title, string directory, string defaultName, ExtensionFilter[] extensions, Action<string> cb);
+    }
+}