Add fuzzing infra

fuzz/Emby.Server.Implementations.Fuzz/Program.cs

@@ -0,0 +1,32 @@
+using System;
+using Emby.Server.Implementations.Library;
+using SharpFuzz;
+
+namespace Emby.Server.Implementations.Fuzz
+{
+    public static class Program
+    {
+        public static void Main(string[] args)
+        {
+            switch (args[0])
+            {
+                case "PathExtensions.TryReplaceSubPath": Run(PathExtensions_TryReplaceSubPath); return;
+                default: throw new ArgumentException($"Unknown fuzzing function: {args[0]}");
+            }
+        }
+
+        private static void Run(Action<string> action) => Fuzzer.OutOfProcess.Run(action);
+
+        private static void PathExtensions_TryReplaceSubPath(string data)
+        {
+            // Stupid, but it worked
+            var parts = data.Split(':');
+            if (parts.Length != 3)
+            {
+                return;
+            }
+
+            _ = PathExtensions.TryReplaceSubPath(parts[0], parts[1], parts[2], out _);
+        }
+    }
+}