fix(tests): pass FakeTranscriptUsageReader to TaskRunner in FailureDiagnosisTests

The cache-token task added an ITranscriptUsageReader ctor param to TaskRunner
while the failure-diagnosis task added this test file. Both branches were green
in isolation; the merged result did not compile.

tests/ClaudeDo.Worker.Tests/Runner/FailureDiagnosisTests.cs

@@ -111,7 +111,7 @@ public sealed class FailureDiagnosisEndToEndTests : IDisposable
         var wt = new WorktreeManager(new GitService(), dbFactory, _cfg, NullLogger<WorktreeManager>.Instance);
         return new TaskRunner(fake, dbFactory, new HubBroadcaster(new CapturingHubContext()), wt,
             new ClaudeArgsBuilder(), _cfg, NullLogger<TaskRunner>.Instance, state, new TaskRunTokenRegistry(),
-            new AttachmentStore(), new FakeSessionSkillSeeder());
+            new AttachmentStore(), new FakeSessionSkillSeeder(), new FakeTranscriptUsageReader());
     }
 
     [Fact]