Reduce repeated ability list reads during pawn ticks

Source/PerformanceFish/AbilityTrackerTickOptimization.cs

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+// Copyright (c) 2026
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+#if V1_6
+using Mono.Cecil;
+using Mono.Cecil.Cil;
+using PerformanceFish.Prepatching;
+
+namespace PerformanceFish;
+
+public sealed class AbilityTrackerTickOptimization : ClassWithFishPrepatches
+{
+	public sealed class AbilitiesTickPatch : FishPrepatch
+	{
+		public override string? Description { get; }
+			= "Reads the pawn ability list once per ability tick instead of twice, while still observing list changes between abilities.";
+
+		public override MethodBase TargetMethodBase { get; }
+			= AccessTools.DeclaredMethod(typeof(Pawn_AbilityTracker), nameof(Pawn_AbilityTracker.AbilitiesTick));
+
+		public override void Transpiler(ILProcessor ilProcessor, ModuleDefinition module)
+			=> ilProcessor.ReplaceBodyWith(AbilitiesTick);
+
+		public static void AbilitiesTick(Pawn_AbilityTracker instance)
+		{
+			for (var i = 0;; i++)
+			{
+				var abilities = instance.AllAbilitiesForReading;
+				if (i >= abilities.Count)
+					return;
+
+				abilities[i].AbilityTick();
+			}
+		}
+	}
+}
+#endif