perf(tests): isolate network E2E and await QUIC cleanup

backend/tests/MoShiro.Backend.Tests/TrustTests.cs

@@ -49,7 +49,7 @@ public sealed class TrustTests : IClassFixture<BackendFixture>
     private async Task<Result<EnrollmentResult>> EnrollAsync(string code, string? genesis, string[]? controllers, string? directory = null)
     {
         directory ??= Path.Combine(Path.GetTempPath(), "moshiro-trust-id-" + Guid.NewGuid().ToString("N"));
-        using var http = new HttpClient();
+        using var http = new HttpClient { Timeout = TimeSpan.FromSeconds(15) };
         return await EnrollmentClient.EnrollAsync(http, _backend.BaseAddress, code, _backend.UniqueName("node"), directory, "0.0.0-test", null, TimeProvider.System, default, genesis, controllers);
     }
 
@@ -128,6 +128,7 @@ public sealed class TrustTests : IClassFixture<BackendFixture>
     }
 
     [Fact]
+    [Trait("Category", "Slow")]
     public async Task APinnedAgent_FollowsTheOperatorSet_WhenThePasskeysChange_AndOnlyWhenTheOperatorSigns()
     {
         Operator op = await OperatorAsync();
@@ -215,6 +216,7 @@ public sealed class TrustTests : IClassFixture<BackendFixture>
     }
 
     [Fact]
+    [Trait("Category", "Slow")]
     public async Task APinnedAgent_ReportsItsOwner_AndThePanelFindsTheAccountAndPasskey()
     {
         // 宿主（属主）要求在节点这一侧：节点把安装时固定的属主报上来，面板顺着凭证 id 反查出它绑定在哪个账户的哪把 passkey 上