fix(worker): emit RunCreated after run row exists

Remove premature RunCreated broadcast from WorkerHub.RunNow and the
duplicate calls in RunAsync retry block and ContinueAsync. RunOnceAsync
now owns the broadcast for every run, fired immediately after the row
insert so the UI never receives an event for a non-existent row.

src/ClaudeDo.Worker/Runner/TaskRunner.cs

@@ -125,7 +125,6 @@ public sealed class TaskRunner
                     var retryConfig = resolvedConfig with { ResumeSessionId = result.SessionId };
                     var retryPrompt = $"The previous attempt failed with:\n\n{result.ErrorMarkdown}\n\nTry again and fix the issues.";
 
-                    await _broadcaster.RunCreated(task.Id, 2, true);
                     var retryResult = await RunOnceAsync(task.Id, slot, runDir, retryConfig, 2, true, retryPrompt, ct);
 
                     if (retryResult.IsSuccess)
@@ -216,7 +215,6 @@ public sealed class TaskRunner
         await _broadcaster.TaskStarted(slot, taskId, now);
 
         var nextRunNumber = lastRun.RunNumber + 1;
-        await _broadcaster.RunCreated(taskId, nextRunNumber, false);
         var result = await RunOnceAsync(taskId, slot, runDir, resolvedConfig, nextRunNumber, false, followUpPrompt, ct);
 
         if (result.IsSuccess)
@@ -255,6 +253,8 @@ public sealed class TaskRunner
             await runRepo.AddAsync(run, ct);
         }
 
+        await _broadcaster.RunCreated(taskId, runNumber, isRetry);
+
         var arguments = _argsBuilder.Build(config);
 
         await using var logWriter = new LogWriter(logPath);