Phase 3 缺陷修复 + 分类管理功能 + ComboBox 主题适配

缺陷修复: 日志自动滚动、StaticResource 顺序修复、ContextMenu PlacementTarget 绑定、PATH 命令支持、异常全量捕获、RefreshData 状态保留、全局崩溃日志

分类管理: 添加/编辑/删除分类，删除时工具移入全部，CategoryEditViewModel/Window

UI 修复: ComboBox 自定义模板，暗色模式弹出层/下拉项主题配色，文本绑定修复

PersonalToolBox.Tests/ViewModels/CategoryEditViewModelTests.cs

@@ -0,0 +1,94 @@
+using Moq;
+using PersonalToolBox.Models;
+using PersonalToolBox.Services;
+using PersonalToolBox.ViewModels;
+
+namespace PersonalToolBox.Tests.ViewModels;
+
+public class CategoryEditViewModelTests
+{
+    private readonly Mock<IDataService> _dataServiceMock = new();
+    private readonly Mock<ILogService> _logServiceMock = new();
+    private readonly AppConfig _config;
+
+    public CategoryEditViewModelTests()
+    {
+        _config = new AppConfig();
+        _dataServiceMock.Setup(d => d.Config).Returns(_config);
+    }
+
+    [Fact]
+    public void Constructor_AddMode_SetsTitle()
+    {
+        var vm = new CategoryEditViewModel(_dataServiceMock.Object, _logServiceMock.Object);
+
+        Assert.Equal("添加分类", vm.WindowTitle);
+        Assert.Empty(vm.Name);
+    }
+
+    [Fact]
+    public void Constructor_EditMode_SetsTitleAndName()
+    {
+        var cat = new Category { Name = "开发工具" };
+        var vm = new CategoryEditViewModel(_dataServiceMock.Object, _logServiceMock.Object, cat);
+
+        Assert.Equal("编辑分类", vm.WindowTitle);
+        Assert.Equal("开发工具", vm.Name);
+    }
+
+    [Fact]
+    public void Save_EmptyName_LogsWarning()
+    {
+        var vm = new CategoryEditViewModel(_dataServiceMock.Object, _logServiceMock.Object);
+
+        vm.SaveCommand.Execute(null);
+
+        _logServiceMock.Verify(x => x.Warning(It.Is<string>(s => s.Contains("名称不能为空"))), Times.Once);
+    }
+
+    [Fact]
+    public void Save_AddMode_AddsCategoryAndCloses()
+    {
+        var vm = new CategoryEditViewModel(_dataServiceMock.Object, _logServiceMock.Object) { Name = "新分类" };
+        bool? closeResult = null;
+        vm.CloseAction = (r) => closeResult = r;
+
+        vm.SaveCommand.Execute(null);
+
+        Assert.True(vm.Saved);
+        Assert.True(closeResult);
+        Assert.Single(_config.Categories);
+        Assert.Equal("新分类", _config.Categories[0].Name);
+        _dataServiceMock.Verify(x => x.Save(), Times.Once);
+    }
+
+    [Fact]
+    public void Save_EditMode_UpdatesCategoryAndCloses()
+    {
+        var cat = new Category { Name = "旧名称" };
+        var vm = new CategoryEditViewModel(_dataServiceMock.Object, _logServiceMock.Object, cat) { Name = "新名称" };
+        bool? closeResult = null;
+        vm.CloseAction = (r) => closeResult = r;
+
+        vm.SaveCommand.Execute(null);
+
+        Assert.True(vm.Saved);
+        Assert.True(closeResult);
+        Assert.Equal("新名称", cat.Name);
+        _dataServiceMock.Verify(x => x.Save(), Times.Once);
+    }
+
+    [Fact]
+    public void Cancel_ClosesWithoutSaving()
+    {
+        var vm = new CategoryEditViewModel(_dataServiceMock.Object, _logServiceMock.Object);
+        bool? closeResult = null;
+        vm.CloseAction = (r) => closeResult = r;
+
+        vm.CancelCommand.Execute(null);
+
+        Assert.False(vm.Saved);
+        Assert.False(closeResult);
+        _dataServiceMock.Verify(x => x.Save(), Times.Never);
+    }
+}