컨텍스트 사용량 링 정렬 회귀 수정

원인: 하단 컨텍스트 사용량 트랙은 22x22 원형인데 arc는 center=15, radius=11 하드코딩으로 더 크게 그려져 오른쪽으로 밀려 보였습니다.

수정: TokenUsageTrack과 TokenUsageArc를 같은 크기와 가운데 정렬로 맞추고, 실제 트랙 지름과 스트로크 두께를 기준으로 중심점·반지름을 계산하는 helper를 추가했습니다. 크기 변경 시에도 arc가 다시 그려지도록 캐시 조건도 보강했습니다.

검증: dotnet build src/AxCopilot/AxCopilot.csproj -c Release -v minimal -p:OutputPath=bin\verify_token_ring_alignment\ -p:IntermediateOutputPath=obj\verify_token_ring_alignment\ (경고 0 / 오류 0), dotnet test src/AxCopilot.Tests/AxCopilot.Tests.csproj -c Release -v minimal --filter ChatWindowSlashPolicyTests -p:OutputPath=bin\verify_token_ring_alignment_tests\ -p:IntermediateOutputPath=obj\verify_token_ring_alignment_tests\ (통과 53)

src/AxCopilot.Tests/Views/ChatWindowSlashPolicyTests.cs

@@ -198,4 +198,21 @@ public class ChatWindowSlashPolicyTests
         var result = method!.Invoke(null, new object?[] { runTab });
         result.Should().Be(expected);
     }
+
+    [Theory]
+    [InlineData(22, 2, 11, 10)]
+    [InlineData(28, 2, 14, 13)]
+    [InlineData(22, 0, 11, 11)]
+    [InlineData(0, 2, 0, 0)]
+    public void CalculateCircularRingMetrics_ShouldAlignCenterlineToTrack(
+        double diameter,
+        double strokeThickness,
+        double expectedCenter,
+        double expectedRadius)
+    {
+        var (center, radius) = ChatWindow.CalculateCircularRingMetrics(diameter, strokeThickness);
+
+        center.Should().Be(expectedCenter);
+        radius.Should().Be(expectedRadius);
+    }
 }

src/AxCopilot/Views/ChatWindow.ContextUsagePresentation.cs

@@ -138,7 +138,24 @@ public partial class ChatWindow
 
         TokenUsageCard.ToolTip = null;
 
-        UpdateCircularUsageArc(TokenUsageArc, usageRatio, 15, 15, 11);
+        var ringDiameter = ResolveTokenUsageRingDiameter();
+        TokenUsageArc.Width = ringDiameter;
+        TokenUsageArc.Height = ringDiameter;
+        var (center, radius) = CalculateCircularRingMetrics(ringDiameter, TokenUsageArc.StrokeThickness);
+        UpdateCircularUsageArc(TokenUsageArc, usageRatio, center, center, radius);
+    }
+
+    private double ResolveTokenUsageRingDiameter()
+    {
+        var actual = TokenUsageTrack?.ActualWidth ?? 0;
+        if (actual > 0)
+            return actual;
+
+        var declared = TokenUsageTrack?.Width ?? 0;
+        if (declared > 0)
+            return declared;
+
+        return TokenUsageArc?.Width > 0 ? TokenUsageArc.Width : 22;
     }
 
     private void TokenUsageCard_MouseEnter(object sender, MouseEventArgs e)

src/AxCopilot/Views/ChatWindow.xaml

@@ -2673,7 +2673,8 @@
                                             MouseLeave="TokenUsageCard_MouseLeave">
                                         <Grid Width="28" Height="28">
                                             <!-- Ring track (subtle background ring) -->
-                                            <Ellipse Width="22" Height="22"
+                                            <Ellipse x:Name="TokenUsageTrack"
+                                                     Width="22" Height="22"
                                                      Stroke="{DynamicResource BorderColor}"
                                                      StrokeThickness="2"
                                                      Opacity="0.45"
@@ -2681,10 +2682,16 @@
                                                      VerticalAlignment="Center"/>
                                             <!-- Usage arc (progress) -->
                                             <Path x:Name="TokenUsageArc"
+                                                  Width="22"
+                                                  Height="22"
                                                   Stroke="{DynamicResource AccentColor}"
                                                   StrokeThickness="2"
                                                   StrokeStartLineCap="Round"
-                                                  StrokeEndLineCap="Round"/>
+                                                  StrokeEndLineCap="Round"
+                                                  Stretch="None"
+                                                  SnapsToDevicePixels="True"
+                                                  HorizontalAlignment="Center"
+                                                  VerticalAlignment="Center"/>
                                             <!-- Hidden data elements (referenced in code) -->
                                             <StackPanel Visibility="Collapsed">
                                                 <TextBlock x:Name="TokenUsagePercentText"

src/AxCopilot/Views/ChatWindow.xaml.cs

@@ -7347,16 +7347,32 @@ public partial class ChatWindow : Window
         return value.ToString("N0");
     }
 
+    internal static (double Center, double Radius) CalculateCircularRingMetrics(double diameter, double strokeThickness)
+    {
+        var safeDiameter = Math.Max(0, diameter);
+        var safeStrokeThickness = Math.Max(0, strokeThickness);
+        var center = safeDiameter / 2;
+        var radius = Math.Max(0, center - (safeStrokeThickness / 2));
+        return (center, radius);
+    }
+
     private double _lastArcRatio = -1;
+    private double _lastArcDiameter = -1;
+    private double _lastArcStrokeThickness = -1;
 
     private void UpdateCircularUsageArc(System.Windows.Shapes.Path path, double ratio, double centerX, double centerY, double radius)
     {
         ratio = Math.Clamp(ratio, 0, 0.9999);
+        var effectiveDiameter = Math.Max(0, radius * 2 + path.StrokeThickness);
 
-        // 비율 변화가 1% 미만이면 렌더링 생략 (250ms마다 호출되므로 불필요한 재생성 방지)
-        if (Math.Abs(ratio - _lastArcRatio) < 0.01)
+        // 비율 변화가 1% 미만이어도 크기나 두께가 바뀌면 다시 그립니다.
+        if (Math.Abs(ratio - _lastArcRatio) < 0.01
+            && Math.Abs(effectiveDiameter - _lastArcDiameter) < 0.01
+            && Math.Abs(path.StrokeThickness - _lastArcStrokeThickness) < 0.01)
             return;
         _lastArcRatio = ratio;
+        _lastArcDiameter = effectiveDiameter;
+        _lastArcStrokeThickness = path.StrokeThickness;
 
         if (ratio <= 0)
         {