feat(state): add SubmitForChildrenAsync (Running -> WaitingForChildren)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/ClaudeDo.Worker.Tests/WaitingForChildrenLifecycleTests.cs

@@ -0,0 +1,129 @@
+using ClaudeDo.Data;
+using ClaudeDo.Data.Models;
+using ClaudeDo.Data.Repositories;
+using ClaudeDo.Worker.Tests.Infrastructure;
+using TaskStatus = ClaudeDo.Data.Models.TaskStatus;
+using Xunit;
+
+namespace ClaudeDo.Worker.Tests;
+
+public sealed class WaitingForChildrenLifecycleTests : IDisposable
+{
+    private readonly DbFixture _db = new();
+    private readonly TestDbContextFactory _factory;
+    private readonly TaskStateServiceBuilder.Built _built;
+
+    public WaitingForChildrenLifecycleTests()
+    {
+        _factory = _db.CreateFactory();
+        _built = TaskStateServiceBuilder.Build(_factory);
+    }
+    public void Dispose() => _db.Dispose();
+
+    private async Task<string> SeedRunningStandaloneAsync()
+    {
+        using var ctx = _db.CreateContext();
+        ctx.Lists.Add(new ListEntity { Id = "l1", Name = "L", CreatedAt = DateTime.UtcNow });
+        ctx.Tasks.Add(new TaskEntity { Id = "p1", ListId = "l1", Title = "Parent",
+            Status = TaskStatus.Running, CreatedAt = DateTime.UtcNow });
+        await ctx.SaveChangesAsync();
+        return "p1";
+    }
+
+    [Fact]
+    public async Task SubmitForChildren_moves_running_task_to_WaitingForChildren()
+    {
+        var id = await SeedRunningStandaloneAsync();
+        var result = await _built.State.SubmitForChildrenAsync(id, DateTime.UtcNow, "ran ok", default);
+        Assert.True(result.Ok);
+        using var ctx = _db.CreateContext();
+        var t = await new TaskRepository(ctx).GetByIdAsync(id);
+        Assert.Equal(TaskStatus.WaitingForChildren, t!.Status);
+        Assert.Equal("ran ok", t.Result);
+        Assert.NotNull(t.FinishedAt);
+    }
+
+    [Fact]
+    public async Task SubmitForChildren_rejects_when_not_running()
+    {
+        var id = await SeedRunningStandaloneAsync();
+        await _built.State.SubmitForChildrenAsync(id, DateTime.UtcNow, null, default);
+        var second = await _built.State.SubmitForChildrenAsync(id, DateTime.UtcNow, null, default);
+        Assert.False(second.Ok);
+    }
+
+    private async Task SeedParentWithChildrenAsync(string parentStatus, params TaskStatus[] childStatuses)
+    {
+        using var ctx = _db.CreateContext();
+        if (!ctx.Lists.Any())
+            ctx.Lists.Add(new ListEntity { Id = "l1", Name = "L", CreatedAt = DateTime.UtcNow });
+        ctx.Tasks.Add(new TaskEntity { Id = "par", ListId = "l1", Title = "Parent",
+            Status = Enum.Parse<TaskStatus>(parentStatus), Result = "parent ran", CreatedAt = DateTime.UtcNow });
+        int i = 0;
+        foreach (var cs in childStatuses)
+            ctx.Tasks.Add(new TaskEntity { Id = $"c{i++}", ListId = "l1", Title = "Child",
+                Status = cs, ParentTaskId = "par", CreatedAt = DateTime.UtcNow });
+        await ctx.SaveChangesAsync();
+    }
+
+    [Fact]
+    public async Task LastChildDone_advances_WaitingForChildren_parent_to_WaitingForReview()
+    {
+        await SeedParentWithChildrenAsync("WaitingForChildren", TaskStatus.Done, TaskStatus.Running);
+        await _built.State.CompleteAsync("c1", DateTime.UtcNow, "child ok", default);
+        using var ctx = _db.CreateContext();
+        var parent = await new TaskRepository(ctx).GetByIdAsync("par");
+        Assert.Equal(TaskStatus.WaitingForReview, parent!.Status);
+    }
+
+    [Fact]
+    public async Task NonLastChild_leaves_parent_in_WaitingForChildren()
+    {
+        await SeedParentWithChildrenAsync("WaitingForChildren", TaskStatus.Running, TaskStatus.Idle);
+        await _built.State.CompleteAsync("c0", DateTime.UtcNow, "ok", default);
+        using var ctx = _db.CreateContext();
+        var parent = await new TaskRepository(ctx).GetByIdAsync("par");
+        Assert.Equal(TaskStatus.WaitingForChildren, parent!.Status);
+    }
+
+    [Fact]
+    public async Task FailedChild_still_advances_parent_and_flags_failure()
+    {
+        await SeedParentWithChildrenAsync("WaitingForChildren", TaskStatus.Done, TaskStatus.Running);
+        await _built.State.FailAsync("c1", DateTime.UtcNow, "boom", default);
+        using var ctx = _db.CreateContext();
+        var parent = await new TaskRepository(ctx).GetByIdAsync("par");
+        Assert.Equal(TaskStatus.WaitingForReview, parent!.Status);
+        Assert.Contains("1 failed", parent.Result!);
+    }
+
+    private async Task SeedParentChildPairAsync(PlanningPhase parentPhase)
+    {
+        using var ctx = _db.CreateContext();
+        if (!ctx.Lists.Any())
+            ctx.Lists.Add(new ListEntity { Id = "l1", Name = "L", CreatedAt = DateTime.UtcNow });
+        ctx.Tasks.Add(new TaskEntity { Id = "par", ListId = "l1", Title = "Parent",
+            Status = TaskStatus.WaitingForChildren, PlanningPhase = parentPhase, CreatedAt = DateTime.UtcNow });
+        ctx.Tasks.Add(new TaskEntity { Id = "kid", ListId = "l1", Title = "Child",
+            Status = TaskStatus.Idle, ParentTaskId = "par", CreatedAt = DateTime.UtcNow });
+        await ctx.SaveChangesAsync();
+    }
+
+    [Fact]
+    public async Task ImprovementChild_can_be_enqueued()
+    {
+        await SeedParentChildPairAsync(PlanningPhase.None);
+        var result = await _built.State.EnqueueAsync("kid", default);
+        Assert.True(result.Ok);
+        using var ctx = _db.CreateContext();
+        Assert.Equal(TaskStatus.Queued, (await new TaskRepository(ctx).GetByIdAsync("kid"))!.Status);
+    }
+
+    [Fact]
+    public async Task PlanningDraftChild_cannot_be_enqueued()
+    {
+        await SeedParentChildPairAsync(PlanningPhase.Active);
+        var result = await _built.State.EnqueueAsync("kid", default);
+        Assert.False(result.Ok);
+    }
+}