feat: in-game error display

Addons/Helper.cs

@@ -1,4 +1,6 @@
 using System;
+using System.IO;
+using UnityEngine;
 using UnityEngine.Analytics;
 
 namespace GBSU.Addons;
@@ -31,4 +33,28 @@ public class Helper
             Plugin.Log.LogError("Could not create rotation folder path: " + e.Message);
         }
     }
+    public static string FilesInRotationDir()
+    {
+        // https://stackoverflow.com/a/14877330
+        DirectoryInfo d = new(RotationFolderPath);
+        FileInfo[] files = d.GetFiles();
+        int number = files.Length;
+
+        // no files?
+        if (number == 0)
+        {
+            return @"No files were found in the directory.";
+        }
+        else
+        {
+            string names = "";
+
+            foreach(FileInfo file in files)
+            {
+                names = file.Name + " " + names;
+            }
+
+            return $"There are {number} files: {names}";
+        }
+    }
 }