Kanske?

Aberwyn/Data/SetupService.cs

@@ -58,8 +58,10 @@ namespace Aberwyn.Data
         {
             public static SetupSettings Load(IHostEnvironment env)
             {
-                var path = Path.Combine(env.ContentRootPath, "infrastructure", "setup.json");
-                var json = File.ReadAllText(path);
+                var dataRoot = Path.Combine(Directory.GetCurrentDirectory(), "data"); // /app/data i containern
+                var filePath = Path.Combine(dataRoot, "infrastructure", "setup.json");
+
+                var json = File.ReadAllText(filePath);
                 return JsonSerializer.Deserialize<SetupSettings>(json)!;
             }