feat(ui): host review actions in the details panel; show review state and diff meter

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/ClaudeDo.Worker.Tests/UiVm/ParseDiffStatTests.cs

@@ -0,0 +1,38 @@
+using ClaudeDo.Ui.ViewModels.Islands;
+
+namespace ClaudeDo.Worker.Tests.UiVm;
+
+public class ParseDiffStatTests
+{
+    [Fact]
+    public void Null_Returns_Zero()
+    {
+        var (add, del) = DetailsIslandViewModel.ParseDiffStat(null);
+        Assert.Equal(0, add);
+        Assert.Equal(0, del);
+    }
+
+    [Fact]
+    public void Empty_Returns_Zero()
+    {
+        var (add, del) = DetailsIslandViewModel.ParseDiffStat("");
+        Assert.Equal(0, add);
+        Assert.Equal(0, del);
+    }
+
+    [Fact]
+    public void Full_Stat_Parses_Both()
+    {
+        var (add, del) = DetailsIslandViewModel.ParseDiffStat("2 files changed, 10 insertions(+), 3 deletions(-)");
+        Assert.Equal(10, add);
+        Assert.Equal(3, del);
+    }
+
+    [Fact]
+    public void Insertions_Only_Returns_Zero_Deletions()
+    {
+        var (add, del) = DetailsIslandViewModel.ParseDiffStat("1 file changed, 5 insertions(+)");
+        Assert.Equal(5, add);
+        Assert.Equal(0, del);
+    }
+}