chore: bajar intervalo scheduler a 20 segundos

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

app/templates/envios_erp.html

@@ -14,7 +14,7 @@
             <button id="btn-scheduler" onclick="switchTab('scheduler')"
                 class="tab-btn flex items-center gap-2 px-4 py-3 text-sm font-medium border-b-2 transition-colors whitespace-nowrap">
                 <i class="fas fa-sync-alt text-xs"></i> Sync Automático
-                <span class="text-xs bg-green-100 text-green-700 px-1.5 py-0.5 rounded-full font-semibold">1 min</span>
+                <span class="text-xs bg-green-100 text-green-700 px-1.5 py-0.5 rounded-full font-semibold">20 seg</span>
             </button>
         </div>
     </div>
@@ -195,7 +195,7 @@ async function pollSchedulerStatus() {
         const live  = document.getElementById('sched-live');
         if (d.running && d.job_exists) {
             dot.className   = 'w-2 h-2 rounded-full bg-green-400 animate-pulse';
-            label.textContent = 'Activo — cada 1 minuto';
+            label.textContent = 'Activo — cada 20 segundos';
             label.className   = 'text-green-600';
         } else {
             dot.className   = 'w-2 h-2 rounded-full bg-red-400';

main.py

@@ -83,7 +83,7 @@ async def startup():
                 None, origen="scheduler", modo="upsert"
             )
 
-    _scheduler.add_job(_job_sync, "interval", minutes=1, id="wa_sync_recientes",
+    _scheduler.add_job(_job_sync, "interval", seconds=20, id="wa_sync_recientes",
                        max_instances=1, coalesce=True)
     _scheduler.start()