fix. 插件安装修复

LanMountainDesktop.Tests/DataLocationResolverTests.cs

@@ -0,0 +1,35 @@
+using LanMountainDesktop.Launcher.Models;
+using Xunit;
+
+namespace LanMountainDesktop.Tests;
+
+public sealed class DataLocationResolverTests : IDisposable
+{
+    private readonly string _appRoot = Path.Combine(
+        Path.GetTempPath(),
+        "LanMountainDesktop.Tests",
+        nameof(DataLocationResolverTests),
+        Guid.NewGuid().ToString("N"));
+
+    [Fact]
+    public void ApplyLocationChoice_PortableWithoutCustomPath_UsesAppRootDesktopDirectory()
+    {
+        Directory.CreateDirectory(_appRoot);
+        var resolver = new DataLocationResolver(_appRoot);
+
+        var applied = resolver.ApplyLocationChoice(DataLocationMode.Portable);
+
+        Assert.True(applied);
+        Assert.Equal(
+            Path.Combine(Path.GetFullPath(_appRoot), "Desktop"),
+            resolver.ResolveDataRoot());
+    }
+
+    public void Dispose()
+    {
+        if (Directory.Exists(_appRoot))
+        {
+            Directory.Delete(_appRoot, recursive: true);
+        }
+    }
+}