feat(data): add TaskRepository.ResetToManualAsync

tests/ClaudeDo.Worker.Tests/Repositories/TaskRepositoryTests.cs

@@ -198,6 +198,35 @@ public sealed class TaskRepositoryTests : IDisposable
         Assert.Equal(TaskStatus.Done, d!.Status);
     }
 
+    [Fact]
+    public async Task ResetToManualAsync_ClearsResultFields_AndSetsStatusManual()
+    {
+        var listId = await CreateListAsync();
+        var task = new TaskEntity
+        {
+            Id = Guid.NewGuid().ToString(),
+            ListId = listId,
+            Title = "T",
+            CreatedAt = DateTime.UtcNow,
+            Status = TaskStatus.Failed,
+            StartedAt = DateTime.UtcNow.AddMinutes(-5),
+            FinishedAt = DateTime.UtcNow,
+            Result = "boom",
+            CommitType = "feat",
+        };
+        await _tasks.AddAsync(task);
+
+        await _tasks.ResetToManualAsync(task.Id);
+
+        using var readCtx = _db.CreateContext();
+        var after = await new TaskRepository(readCtx).GetByIdAsync(task.Id);
+        Assert.NotNull(after);
+        Assert.Equal(TaskStatus.Manual, after!.Status);
+        Assert.Null(after.StartedAt);
+        Assert.Null(after.FinishedAt);
+        Assert.Null(after.Result);
+    }
+
     [Fact]
     public async Task GetEffectiveTagsAsync_Returns_Union_Of_ListTags_And_TaskTags()
     {