改了一亿个东西，修了一亿个 BUG

Utils/ImmutableArrayExtensions.cs

@@ -0,0 +1,20 @@
+using System;
+using System.Collections.Immutable;
+
+namespace AnotherReplayReader.Utils
+{
+    static class ImmutableArrayExtensions
+    {
+        public static int? FindIndex<T>(this in ImmutableArray<T> a, Predicate<T> p)
+        {
+            for (var i = 0; i < a.Length; ++i)
+            {
+                if (p(a[i]))
+                {
+                    return i;
+                }
+            }
+            return null;
+        }
+    }
+}