feat(claude-do): Merge-Session soll die Queue selbst beobachten statt fertige

## WO — verifiziert am 2026-09-02, nicht neu suchen

- Merge-Phasen-Prompt: `src/ClaudeDo.Data/PromptFiles.cs`, Konstante `MergeHelperMergeDefault` (ab Z. 495). Der neue Warte-Abschnitt gehört zwischen "## Verify once — after the last merge" (Z. 526) und "## Handoff / end" (Z. 542) — also nach dem Verify, vor der Handoff-Entscheidung.
- Brief-Template: `MergeHelperInitialDefault` (Z. 555) und `Mer

ClaudeDo-Task: 1788adc4-c671-4942-ab78-1ef1812da494

src/ClaudeDo.Data/PromptFiles.cs

@@ -548,6 +548,30 @@ public static class PromptFiles
 
         Allow at most ONE rerun per task in this session.
 
+        ## Keep watching the queue
+
+        Do not assume the tasks you were handed are the only ones that matter. A prior Wait session
+        can already have finished before every one of its tasks actually reached a terminal status,
+        or new tasks can still be running when you start — merging only what happened to be ready the
+        moment you looked in and then stopping is how work silently falls through the cracks.
+
+        Before you go to Handoff / end, call get_queue_state and check whether any task id from your
+        brief still shows up in activeSlots or waitingTaskIds. If none do, your list is clear — go to
+        Handoff / end now.
+
+        If some do, call wait_for_task_change with exactly those still-busy task ids,
+        timeoutSeconds=900, treatWaitingForChildrenAsBusy=true. When it reports a change, go back to
+        Phase 4 and merge/review whatever it now says is WaitingForReview, then repeat this check.
+
+        This is NOT a `sleep`-and-poll loop — never write your own retry/sleep loop around get_task or
+        get_queue_state. wait_for_task_change already blocks server-side and reports progress so it
+        survives your own client's idle-silence abort; that is the only waiting mechanism allowed here.
+
+        Hard cap: stop after at most THREE consecutive wait_for_task_change calls made this way (three
+        900s timeouts ≈ 45 minutes total), even if tasks are still busy. When you stop — because the
+        queue cleared or because you hit the cap — report whatever is still Queued/Running in the
+        summary below and proceed to Handoff / end exactly as if this section didn't exist.
+
         ## Handoff / end
 
         - If you started any reruns: call handoff_list_handler(taskId, <the rerun task ids>, nextPhase: "wait_final"), then stop your turn immediately — do not merge anything yet that you just restarted. Do NOT submit this run for review yet — the chain isn't finished.

src/ClaudeDo.Worker/Runner/InteractiveLaunchSpecService.cs

@@ -284,12 +284,12 @@ public sealed class InteractiveLaunchSpecService
             throw new InvalidOperationException($"list '{list.Name}' has no existing working directory");
         repoDir = TrimTrailingSeparator(repoDir);
 
-        var briefLines = new List<string>();
+        var briefEntries = new List<(TaskEntity Task, string Line)>();
         foreach (var id in taskIds)
         {
             var task = await taskRepo.GetByIdAsync(id, ct)
                 ?? throw new KeyNotFoundException($"Task not found: {id}");
-            briefLines.Add(RenderBriefEntry(task));
+            briefEntries.Add((task, RenderBriefEntry(task)));
         }
 
         var sessionDir = Path.Combine(Paths.AppDataRoot(), "merge-helper-sessions", Guid.NewGuid().ToString());
@@ -305,7 +305,7 @@ public sealed class InteractiveLaunchSpecService
                 ["scope"] = $"List: {list.Name}",
                 ["repo"] = repoDir,
                 ["handlerTaskId"] = handlerTaskId,
-                ["tasks"] = string.Join("\n", briefLines),
+                ["tasks"] = RenderGroupedBrief(briefEntries),
             }), ct);
 
         var resolvedClaude = WindowsTerminalLauncher.Resolve(_claudePath)
@@ -379,12 +379,12 @@ public sealed class InteractiveLaunchSpecService
             throw new InvalidOperationException($"list '{list.Name}' has no existing working directory");
         repoDir = TrimTrailingSeparator(repoDir);
 
-        var briefLines = new List<string>();
+        var briefEntries = new List<(TaskEntity Task, string Line)>();
         foreach (var id in survivingTaskIds)
         {
             var task = await taskRepo.GetByIdAsync(id, ct)
                 ?? throw new KeyNotFoundException($"Task not found: {id}");
-            briefLines.Add($"- [{task.Status}] {task.Title} (id: {task.Id})");
+            briefEntries.Add((task, $"- [{task.Status}] {task.Title} (id: {task.Id})"));
         }
 
         var sessionDir = Path.Combine(Paths.AppDataRoot(), "merge-helper-sessions", Guid.NewGuid().ToString());
@@ -408,7 +408,7 @@ public sealed class InteractiveLaunchSpecService
                 ["scope"] = $"List: {list.Name}",
                 ["repo"] = repoDir,
                 ["handlerTaskId"] = taskId,
-                ["tasks"] = string.Join("\n", briefLines),
+                ["tasks"] = RenderGroupedBrief(briefEntries),
                 ["finalNote"] = finalNote,
             }), ct);
 
@@ -444,6 +444,27 @@ public sealed class InteractiveLaunchSpecService
     // at all. ListRepository normalizes on write now, but rows written before that still carry one.
     private static string TrimTrailingSeparator(string dir) => Paths.TrimTrailingSeparator(dir)!;
 
+    // A task the picker would still touch (or is mid-run) vs. one that already landed
+    // somewhere terminal-ish. Split the brief on this so a handler session picking up after a
+    // Wait phase can see at a glance which of its tasks are actually ready to review and which
+    // are still moving underneath it -- the flat list this replaces made every task look
+    // equally "done" regardless of status.
+    private static readonly TaskStatus[] StillRunningStatuses =
+        { TaskStatus.Queued, TaskStatus.Running, TaskStatus.WaitingForChildren };
+
+    private static string RenderGroupedBrief(IReadOnlyList<(TaskEntity Task, string Line)> entries)
+    {
+        var finished = entries.Where(e => !StillRunningStatuses.Contains(e.Task.Status)).Select(e => e.Line).ToList();
+        var running = entries.Where(e => StillRunningStatuses.Contains(e.Task.Status)).Select(e => e.Line).ToList();
+
+        var sections = new List<string>();
+        if (finished.Count > 0)
+            sections.Add("### Done / waiting for review\n" + string.Join("\n", finished));
+        if (running.Count > 0)
+            sections.Add("### Still running\n" + string.Join("\n", running));
+        return string.Join("\n\n", sections);
+    }
+
     // Renders one task as a brief list item. A description can itself be arbitrary Markdown
     // (headings, lists, fenced code) — those must not merge into the brief's own task list, so
     // the description is placed in a fenced code block indented to the list item's continuation