fix: remove folder icons, add single run for maintenance, fix batch 400

- Remove AddToFolderMenu from grid/list/table library views (folders removed)
- Add single "Run" button to MaintenanceFlowDetailPage alongside Batch Launch
- Change seed script to publish maintenance flows (batch rejects drafts)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/pages/MaintenanceFlowDetailPage.tsx

@@ -99,10 +99,16 @@ export default function MaintenanceFlowDetailPage() {
             Edit Flow
           </button>
           <button
-            onClick={() => setShowBatchModal(true)}
+            onClick={() => navigate(`/flows/${id}/navigate`)}
             className="flex items-center gap-1.5 rounded-lg bg-gradient-brand px-4 py-2 text-[0.875rem] font-medium text-white shadow-lg shadow-primary/20 hover:opacity-90"
           >
             <Play className="h-3.5 w-3.5" />
+            Run
+          </button>
+          <button
+            onClick={() => setShowBatchModal(true)}
+            className="flex items-center gap-1.5 rounded-lg border border-border px-3 py-2 text-[0.875rem] text-muted-foreground hover:bg-accent hover:text-foreground"
+          >
             Batch Launch
           </button>
         </div>