chore: update watchlist features and fixes

templates/watchlist.html

@@ -148,17 +148,29 @@
             const stopBtn = document.getElementById('stopSchedulerBtn');
             const nextRunInfo = document.getElementById('nextRunInfo');
 
+            // nextRunInfo is required, but buttons are optional
+            if (!nextRunInfo) {
+                console.warn('nextRunInfo element not found');
+                return;
+            }
+
             if (status.running) {
-                startBtn.style.display = 'none';
-                stopBtn.style.display = 'inline-block';
+                // Update buttons if they exist
+                if (startBtn) startBtn.style.display = 'none';
+                if (stopBtn) stopBtn.style.display = 'inline-block';
 
                 if (status.next_run) {
                     const nextRun = new Date(status.next_run);
                     nextRunInfo.innerHTML = `✓ En cours<br>Prochaine vérification: ${nextRun.toLocaleString('fr-FR')}`;
+                } else {
+                    // Scheduler running but no next_run yet (just started)
+                    const interval = status.settings?.check_interval_hours || 6;
+                    nextRunInfo.innerHTML = `✓ En cours<br>Vérification toutes les ${interval}h`;
                 }
             } else {
-                startBtn.style.display = 'inline-block';
-                stopBtn.style.display = 'none';
+                // Update buttons if they exist
+                if (startBtn) startBtn.style.display = 'inline-block';
+                if (stopBtn) stopBtn.style.display = 'none';
                 nextRunInfo.innerHTML = '⏸️ Arrêté';
             }
         }