chore(claude-do): merge [C4] Rebase-after-Merge sichtbar machen + WorktreeMaintenanc

ClaudeDo-Task: 0a64e32d-6308-4f2d-a69e-fb8b3cabd01a

src/ClaudeDo.Worker/Lifecycle/TaskMergeService.cs

@@ -64,6 +64,7 @@ public sealed class TaskMergeService
     // Phase tokens for the OperationProgress broadcast — stable identifiers, localized by the UI.
     public const string PhaseMerging   = "merging";
     public const string PhaseVerifying = "verifying";
+    public const string PhaseRebasing  = "rebasing";
 
     public const string PreviewClean       = "clean";
     public const string PreviewConflict    = "conflict";
@@ -296,9 +297,15 @@ public sealed class TaskMergeService
             var tasks = await new TaskRepository(ctx).GetByListIdAsync(list.Id, ct);
             candidates = tasks.Where(t => t.Id != mergedTask.Id && t.Status == TaskStatus.WaitingForReview).ToList();
         }
+        if (candidates.Count == 0) return;
 
-        foreach (var candidate in candidates)
-            await RebaseOneIfOverlappingAsync(candidate, targetBranch, newTargetTip, landedFiles, ct);
+        // Runs where the stalled "Merging…" phase would otherwise sit unchanged in the UI while
+        // this loop does real (if best-effort) work — see the correction note in the task spec.
+        for (var i = 0; i < candidates.Count; i++)
+        {
+            await _broadcaster.OperationProgress(mergedTask.Id, PhaseRebasing, i + 1, candidates.Count);
+            await RebaseOneIfOverlappingAsync(candidates[i], targetBranch, newTargetTip, landedFiles, ct);
+        }
     }
 
     private async Task RebaseOneIfOverlappingAsync(

src/ClaudeDo.Worker/Worktrees/WorktreeMaintenanceService.cs

@@ -1,6 +1,7 @@
 using ClaudeDo.Data;
 using ClaudeDo.Data.Git;
 using ClaudeDo.Data.Models;
+using ClaudeDo.Worker.Hub;
 using Microsoft.EntityFrameworkCore;
 
 namespace ClaudeDo.Worker.Worktrees;
@@ -11,20 +12,31 @@ public sealed class WorktreeMaintenanceService
     public sealed record ResetResult(int Removed, int TasksAffected, bool Blocked, int RunningTasks, IReadOnlyList<string> RemovedTaskIds);
     public sealed record ForceRemoveResult(bool Removed, string? Reason, bool BranchDeleted);
 
+    // opKey/phase for the OperationProgress broadcast. Not task-bound, so opKey is a stable
+    // string rather than a task id — mirrors "startup-recovery"/"worktree-cleanup" in HubBroadcaster.
+    public const string OpKey = "worktree-maintenance";
+    public const string PhaseMaintaining = "maintaining-worktrees";
+
     private readonly IDbContextFactory<ClaudeDoDbContext> _dbFactory;
     private readonly GitService _git;
     private readonly ILogger<WorktreeMaintenanceService> _logger;
+    private readonly HubBroadcaster? _broadcaster;
 
     public WorktreeMaintenanceService(
         IDbContextFactory<ClaudeDoDbContext> dbFactory,
         GitService git,
-        ILogger<WorktreeMaintenanceService> logger)
+        ILogger<WorktreeMaintenanceService> logger,
+        HubBroadcaster? broadcaster = null)
     {
         _dbFactory = dbFactory;
         _git = git;
         _logger = logger;
+        _broadcaster = broadcaster;
     }
 
+    private Task ReportProgress(int current, int total) =>
+        _broadcaster?.OperationProgress(OpKey, PhaseMaintaining, current, total) ?? Task.CompletedTask;
+
     public async Task<CleanupResult> CleanupFinishedAsync(string? listId = null, CancellationToken ct = default)
     {
         using var context = _dbFactory.CreateDbContext();
@@ -41,13 +53,14 @@ public sealed class WorktreeMaintenanceService
 
         int removed = 0;
         var removedTaskIds = new List<string>();
-        foreach (var row in rows)
+        for (var i = 0; i < rows.Count; i++)
         {
-            var (rowRemoved, _) = await TryRemoveAsync(row, force: false, ct);
+            await ReportProgress(i + 1, rows.Count);
+            var (rowRemoved, _) = await TryRemoveAsync(rows[i], force: false, ct);
             if (rowRemoved)
             {
                 removed++;
-                removedTaskIds.Add(row.TaskId);
+                removedTaskIds.Add(rows[i].TaskId);
             }
         }
         return new CleanupResult(removed, removedTaskIds);
@@ -70,13 +83,14 @@ public sealed class WorktreeMaintenanceService
 
         int removed = 0;
         var removedTaskIds = new List<string>();
-        foreach (var row in rows)
+        for (var i = 0; i < rows.Count; i++)
         {
-            var (rowRemoved, _) = await TryRemoveAsync(row, force: true, ct);
+            await ReportProgress(i + 1, rows.Count);
+            var (rowRemoved, _) = await TryRemoveAsync(rows[i], force: true, ct);
             if (rowRemoved)
             {
                 removed++;
-                removedTaskIds.Add(row.TaskId);
+                removedTaskIds.Add(rows[i].TaskId);
             }
         }
         return new ResetResult(removed, rows.Count, Blocked: false, RunningTasks: 0, removedTaskIds);