feat(mission-control): give the list handler its own review task

"Let Claude handle it" now creates one ClaudeDo task per run to host the
ConPTY session (Idle/IsManual, never queued) instead of an untracked
ad-hoc tile, so the run has a real title, diff, and review outcome.
Since the handler merges its own changes straight into the list's
working dir, the task never gets a WorktreeEntity; its review range
lives as new HandlerBaseCommit/HandlerHeadCommit columns on TaskEntity
instead, reusing the existing commit-range diff machinery and keeping
it out of the worktrees overview entirely.

tests/ClaudeDo.Ui.Tests/ViewModels/DetailsIslandHandlerRangeTests.cs

@@ -0,0 +1,105 @@
+using ClaudeDo.Data;
+using ClaudeDo.Data.Models;
+using ClaudeDo.Ui.Services;
+using ClaudeDo.Ui.ViewModels.Islands;
+using Microsoft.EntityFrameworkCore;
+using TaskStatus = ClaudeDo.Data.Models.TaskStatus;
+
+namespace ClaudeDo.Ui.Tests.ViewModels;
+
+/// Covers the worktree-less "list handler" host task (Mission Control's "Let Claude handle
+/// it"): it has no WorktreeEntity, so the detail pane's review range must fall back to
+/// TaskEntity.HandlerBaseCommit/HandlerHeadCommit, and the merge/diff card must still render.
+public class DetailsIslandHandlerRangeTests : IDisposable
+{
+    private readonly string _dbPath;
+
+    public DetailsIslandHandlerRangeTests()
+    {
+        _dbPath = Path.Combine(Path.GetTempPath(), $"claudedo_details_handler_test_{Guid.NewGuid():N}.db");
+        using var ctx = NewContext();
+        ctx.Database.EnsureCreated();
+    }
+
+    public void Dispose()
+    {
+        try { File.Delete(_dbPath); } catch { }
+        try { File.Delete(_dbPath + "-wal"); } catch { }
+        try { File.Delete(_dbPath + "-shm"); } catch { }
+    }
+
+    private ClaudeDoDbContext NewContext()
+    {
+        var opts = new DbContextOptionsBuilder<ClaudeDoDbContext>()
+            .UseSqlite($"Data Source={_dbPath}")
+            .Options;
+        return new ClaudeDoDbContext(opts);
+    }
+
+    private sealed class TestDbFactory : IDbContextFactory<ClaudeDoDbContext>
+    {
+        private readonly Func<ClaudeDoDbContext> _create;
+        public TestDbFactory(Func<ClaudeDoDbContext> create) => _create = create;
+        public ClaudeDoDbContext CreateDbContext() => _create();
+    }
+
+    private sealed class NullServiceProvider : IServiceProvider
+    {
+        public object? GetService(Type serviceType) => null;
+    }
+
+    private sealed class StubNotesApi : ClaudeDo.Ui.Services.Interfaces.INotesApi
+    {
+        public Task<List<DailyNoteDto>> ListAsync(DateOnly day) =>
+            Task.FromResult(new List<DailyNoteDto>());
+        public Task<DailyNoteDto?> AddAsync(DateOnly day, string text) =>
+            Task.FromResult<DailyNoteDto?>(null);
+        public Task UpdateAsync(string id, string text) => Task.CompletedTask;
+        public Task DeleteAsync(string id) => Task.CompletedTask;
+    }
+
+    private sealed class FakeWorkerClient : StubWorkerClient
+    {
+        public override bool IsConnected => true;
+    }
+
+    private DetailsIslandViewModel BuildVm()
+    {
+        var factory = new TestDbFactory(NewContext);
+        return new DetailsIslandViewModel(
+            factory, new FakeWorkerClient(), new NullServiceProvider(), new StubNotesApi(), new MergeCoordinator());
+    }
+
+    [Fact]
+    public async Task Bind_WorktreeLessHandlerTask_FallsBackToHandlerCommitRange_AndShowsMergeSection()
+    {
+        const string listId = "list-1";
+        const string taskId = "handler-task-1";
+
+        await using (var ctx = NewContext())
+        {
+            ctx.Lists.Add(new ListEntity { Id = listId, Name = "L", WorkingDir = @"C:\repo", CreatedAt = DateTime.UtcNow });
+            ctx.Tasks.Add(new TaskEntity
+            {
+                Id = taskId, ListId = listId, Title = "List handler: L",
+                Status = TaskStatus.WaitingForReview, IsManual = true,
+                HandlerBaseCommit = "base123", HandlerHeadCommit = "head456",
+                CreatedAt = DateTime.UtcNow,
+            });
+            await ctx.SaveChangesAsync();
+        }
+
+        var vm = BuildVm();
+        vm.Bind(new TaskRowViewModel { Id = taskId, Status = TaskStatus.WaitingForReview });
+
+        var deadline = DateTime.UtcNow.AddSeconds(5);
+        while (DateTime.UtcNow < deadline && vm.WorktreeBaseCommit is null)
+            await Task.Delay(20);
+
+        Assert.Equal("base123", vm.WorktreeBaseCommit);
+        Assert.Equal("head456", vm.WorktreeHeadCommit);
+        Assert.Null(vm.WorktreePath);
+        Assert.True(vm.Merge.ShowMergeSection);
+        Assert.True(vm.Merge.HasReviewableDiff);
+    }
+}