@

Add MrGameEng.AI utility-AI module; format codebase with CSharpier

New MrGameEng.AI module (ResponseCurve, Consideration, UtilityAction,
UtilityAi selector, Blackboard) plus CSharpier formatting applied across
the whole engine. Documents the CSharpier convention in CLAUDE.md.
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tests/MrGameEng.AI.Tests/BlackboardTests.cs

@@ -0,0 +1,64 @@
+using Microsoft.Xna.Framework;
+using MrGameEng.AI;
+using Xunit;
+
+namespace MrGameEng.AI.Tests;
+
+public class BlackboardTests
+{
+    [Fact]
+    public void SetThenTryGet_RoundTripsTypedValues()
+    {
+        var board = new Blackboard();
+        board.Set("target", new Vector2(3f, 4f));
+
+        Assert.True(board.TryGet<Vector2>("target", out var value));
+        Assert.Equal(new Vector2(3f, 4f), value);
+    }
+
+    [Fact]
+    public void TryGet_ReturnsFalse_OnMissingKeyOrTypeMismatch()
+    {
+        var board = new Blackboard();
+        board.Set("count", 5);
+
+        Assert.False(board.TryGet<int>("missing", out _));
+        Assert.False(board.TryGet<string>("count", out _)); // wrong type
+    }
+
+    [Fact]
+    public void GetOrDefault_FallsBackWhenAbsent()
+    {
+        var board = new Blackboard();
+
+        Assert.Equal(42, board.GetOrDefault("hp", 42));
+        board.Set("hp", 7);
+        Assert.Equal(7, board.GetOrDefault("hp", 42));
+    }
+
+    [Fact]
+    public void Set_OverwritesExistingValue()
+    {
+        var board = new Blackboard();
+        board.Set("k", 1);
+        board.Set("k", 2);
+
+        Assert.Equal(2, board.GetOrDefault("k", 0));
+        Assert.Equal(1, board.Count);
+    }
+
+    [Fact]
+    public void RemoveAndClear_DropKeys()
+    {
+        var board = new Blackboard();
+        board.Set("a", 1);
+        board.Set("b", 2);
+
+        Assert.True(board.Remove("a"));
+        Assert.False(board.Remove("a"));
+        Assert.True(board.Has("b"));
+
+        board.Clear();
+        Assert.Equal(0, board.Count);
+    }
+}