Add fuzzing infra

fuzz/Jellyfin.Server.Fuzz/Program.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Collections.Generic;
+using Jellyfin.Server.Middleware;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.Features;
+using Microsoft.Extensions.Primitives;
+using SharpFuzz;
+
+namespace Emby.Server.Implementations.Fuzz
+{
+    public static class Program
+    {
+        public static void Main(string[] args)
+        {
+            switch (args[0])
+            {
+                case "UrlDecodeQueryFeature": Run(UrlDecodeQueryFeature); return;
+                default: throw new ArgumentException($"Unknown fuzzing function: {args[0]}");
+            }
+        }
+
+        private static void Run(Action<string> action) => Fuzzer.OutOfProcess.Run(action);
+
+        private static void UrlDecodeQueryFeature(string data)
+        {
+            var dict = new Dictionary<string, StringValues>
+            {
+                { data, StringValues.Empty }
+            };
+            _ = new UrlDecodeQueryFeature(new QueryFeature(new QueryCollection(dict)));
+        }
+    }
+}