Fix BenchmarkDotNet: fresh solver per iteration via IterationSetup + RunStrategy.Monitoring

Previous run measured cached TT lookups (microseconds). Now measures real cold search (milliseconds).

Baseline results on main:

  Example1 (empty board):     146ms,   178 MB allocated

  Example2 (four pieces):     176ms,   176 MB allocated

  Example3 (twelve pieces):  1300ms,  1630 MB allocated

  Example5 (complex midgame):13892ms, 15907 MB allocated

Key finding: GC pressure is the dominant bottleneck (1.28M Gen0 collections for Example5).

Author: boraaros

Alligator.Benchmark/Properties/launchSettings.json

@@ -0,0 +1,12 @@
+{
+  "profiles": {
+    "Diagnostic": {
+      "commandName": "Project",
+      "commandLineArgs": ""
+    },
+    "BenchmarkDotNet": {
+      "commandName": "Project",
+      "commandLineArgs": "--benchmark"
+    }
+  }
+}

Alligator.Benchmark/SolverBenchmarks.cs

@@ -2,33 +2,40 @@
 using Alligator.SixMaking.Model;
 using Alligator.Solver;
 using BenchmarkDotNet.Attributes;
+using BenchmarkDotNet.Engines;
 
 namespace Alligator.Benchmark
 {
     [MemoryDiagnoser]
-    [SimpleJob(warmupCount: 1, iterationCount: 5)]
+    [SimpleJob(RunStrategy.Monitoring, warmupCount: 1, iterationCount: 5)]
     public class SolverBenchmarks
     {
+        private SolverProvider<IPosition, Step> solverFactory = null!;
         private ISolver<Step> solver = null!;
         private IList<Step> example1History = null!;
         private IList<Step> example2History = null!;
         private IList<Step> example3History = null!;
         private IList<Step> example5History = null!;
 
         [GlobalSetup]
-        public void Setup()
+        public void GlobalSetup()
         {
             var rules = new Rules(new StepPool(), new MovingRules());
             var solverConfiguration = new Configuration();
-            var solverFactory = new SolverProvider<IPosition, Step>(rules, solverConfiguration);
-            solver = solverFactory.Create();
+            solverFactory = new SolverProvider<IPosition, Step>(rules, solverConfiguration);
 
             example1History = BuildHistory(Example1());
             example2History = BuildHistory(Example2());
             example3History = BuildHistory(Example3());
             example5History = BuildHistory(Example5());
         }
 
+        [IterationSetup]
+        public void IterationSetup()
+        {
+            solver = solverFactory.Create();
+        }
+
         [Benchmark(Description = "Example1 - Empty board")]
         public Step Example1_EmptyBoard() => solver.OptimizeNextStep(example1History);