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.

src/ClaudeDo.Worker/Runner/InteractiveLaunchSpecService.cs

@@ -1,4 +1,5 @@
 using ClaudeDo.Data;
+using ClaudeDo.Data.Git;
 using ClaudeDo.Data.Models;
 using ClaudeDo.Data.Repositories;
 using ClaudeDo.Worker.Config;
@@ -29,6 +30,7 @@ public sealed class InteractiveLaunchSpecService : IInteractiveLaunchSpecService
     private readonly ISessionSkillSeeder _skillSeeder;
     private readonly ISessionSkillRegistry _skillRegistry;
     private readonly WorktreeManager _wtManager;
+    private readonly GitService _git;
     private readonly string _claudePath;
 
     public InteractiveLaunchSpecService(
@@ -36,12 +38,14 @@ public sealed class InteractiveLaunchSpecService : IInteractiveLaunchSpecService
         ISessionSkillSeeder skillSeeder,
         ISessionSkillRegistry skillRegistry,
         WorktreeManager wtManager,
+        GitService git,
         WorkerConfig cfg)
     {
         _dbFactory = dbFactory;
         _skillSeeder = skillSeeder;
         _skillRegistry = skillRegistry;
         _wtManager = wtManager;
+        _git = git;
         _claudePath = cfg.ClaudeBin;
     }
 
@@ -248,6 +252,57 @@ public sealed class InteractiveLaunchSpecService : IInteractiveLaunchSpecService
         return new LaunchSpec(repoDir, resolvedClaude, args, env);
     }
 
+    // Creates the ClaudeDo task that hosts a list-handler run (Mission Control's "Let Claude
+    // handle it") and stamps the list repo's current HEAD as the review range's base commit.
+    // The handler never gets its own worktree -- it commits straight to the list's working
+    // dir -- so this HandlerBaseCommit/HandlerHeadCommit pair (see TaskEntity) is what lets the
+    // normal diff/get_task_diff paths show what the run changed once it submits for review.
+    // IsManual=true so the queue picker, daily prep, and the "send to queue"/"refine" UI
+    // affordances all skip it, matching the "reminder only a human/ConPTY session can act on"
+    // semantics IsManual already carries elsewhere; the ConPTY session itself is still allowed.
+    public async Task<string> CreateMergeHelperTaskAsync(
+        IReadOnlyList<string> taskIds, string listId, string title, string descriptionHeader, CancellationToken ct)
+    {
+        if (taskIds.Count == 0)
+            throw new InvalidOperationException("No tasks selected for the list handler.");
+
+        await using var ctx = await _dbFactory.CreateDbContextAsync(ct);
+        var listRepo = new ListRepository(ctx);
+        var taskRepo = new TaskRepository(ctx);
+
+        var list = await listRepo.GetByIdAsync(listId, ct)
+            ?? throw new KeyNotFoundException($"List not found: {listId}");
+
+        var repoDir = list.WorkingDir;
+        if (string.IsNullOrEmpty(repoDir) || !Directory.Exists(repoDir))
+            throw new InvalidOperationException($"list '{list.Name}' has no existing working directory");
+
+        var descriptionLines = new List<string>();
+        foreach (var id in taskIds)
+        {
+            var task = await taskRepo.GetByIdAsync(id, ct);
+            if (task is not null) descriptionLines.Add($"- [{task.Status}] {task.Title} (id: {task.Id})");
+        }
+
+        var baseCommit = await _git.RevParseHeadAsync(repoDir, ct);
+
+        var handlerTask = new TaskEntity
+        {
+            Id = Guid.NewGuid().ToString(),
+            ListId = listId,
+            Title = title,
+            Description = descriptionLines.Count > 0
+                ? $"{descriptionHeader}\n{string.Join("\n", descriptionLines)}"
+                : descriptionHeader,
+            IsManual = true,
+            HandlerBaseCommit = baseCommit,
+            CreatedAt = DateTime.UtcNow,
+        };
+        await taskRepo.AddAsync(handlerTask, ct);
+
+        return handlerTask.Id;
+    }
+
     // The reasoning effort configured for a model in Settings → General. Falls back to the shipped
     // preset for that model, so a missing/malformed settings row can never block a launch.
     private static string EffortFor(AppSettingsEntity settings, string? model)

src/ClaudeDo.Worker/Runner/Interfaces/IInteractiveLaunchSpecService.cs

@@ -34,4 +34,12 @@ public interface IInteractiveLaunchSpecService
     /// Throws KeyNotFoundException if the list doesn't exist; InvalidOperationException if
     /// taskIds is empty or the list has no existing working directory.</summary>
     Task<LaunchSpec> BuildForMergeHelperAsync(IReadOnlyList<string> taskIds, string listId, CancellationToken ct);
+
+    /// <summary>Creates the ClaudeDo task that hosts a list-handler run (Mission Control's
+    /// "Let Claude handle it") and stamps the list repo's current HEAD as the review range's
+    /// base commit (see TaskEntity.HandlerBaseCommit). Returns the new task's id. Throws
+    /// KeyNotFoundException if the list doesn't exist; InvalidOperationException if taskIds
+    /// is empty or the list has no existing working directory.</summary>
+    Task<string> CreateMergeHelperTaskAsync(
+        IReadOnlyList<string> taskIds, string listId, string title, string descriptionHeader, CancellationToken ct);
 }