How do I load images after building?

I don't have much experience with Javascript and therefore I can't aid you much on that part, but I recently created my own script capable of reading .wav files from an external folder using System.IO. I presume you can modify this to fit yours, but as stated this is written in C#.

The example code work as follows: First it check whether the folder "SoundFolder" exist, if it doesn't it simply creates a new one. This folder is located in the same folder as the build. I then get a list of all files wihtin that folder and filter all other files. that doesn't have the .wav extension to it. I am not even sure whether this would work on Mac.

 public void Initialize()
         {
             DirectoryInfo directoryInformation = new DirectoryInfo("SoundFolder");
             if(!directoryInformation.Exists)
                 directoryInformation.Create();
     
             FileInfo[] fileList = directoryInformation.GetFiles();
     
             foreach (FileInfo file in fileList)
             {
                 if (file.Extension == ".wav")
                 {
                    SomeCode();          
                 }
             }
         }