fix: restore archive completion notification polling

Track monthly archive generation by generated_archive_id and poll notifications until completed/failed (up to timeout) instead of short PDF polling only. This restores completed ZIP notifications for calendar archive actions when generation takes longer.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

frontend/src/stores/fleetDashboardStore.js

@@ -28,6 +28,9 @@ const DASHBOARD_FETCH_TTL_MS = 30_000; // 30 sekundi
 let dbPromise = null;
 let syncListenerStarted = false;
 let isSyncInProgress = false;
+const archiveNotificationPollers = new Map();
+const ARCHIVE_NOTIFICATION_POLL_INTERVAL_MS = 10_000;
+const ARCHIVE_NOTIFICATION_POLL_TIMEOUT_MS = 15 * 60 * 1000;
 
 function isBrowser() {
     return typeof window !== 'undefined';
@@ -866,6 +869,70 @@ function _schedulePdfNotificationPolling() {
     });
 }
 
+function _findCompletedArchiveNotification(notifications, generatedArchiveId) {
+    if (!generatedArchiveId || !Array.isArray(notifications)) {
+        return null;
+    }
+    return notifications.find((notification) => {
+        const metadata = notification?.metadata || {};
+        return metadata.entity_type === 'fleet_archive'
+            && String(metadata.generated_archive_id || '') === String(generatedArchiveId)
+            && ['completed', 'failed'].includes(String(metadata.stage || ''));
+    }) || null;
+}
+
+function _clearArchiveNotificationPoller(generatedArchiveId) {
+    const key = String(generatedArchiveId || '');
+    const handles = archiveNotificationPollers.get(key);
+    if (!handles) {
+        return;
+    }
+    window.clearInterval(handles.intervalId);
+    window.clearTimeout(handles.timeoutId);
+    archiveNotificationPollers.delete(key);
+}
+
+function _scheduleArchiveNotificationPolling(generatedArchiveId = null) {
+    if (!isBrowser()) return;
+    if (!generatedArchiveId) {
+        [5000, 20000, 60000].forEach((delay) => {
+            setTimeout(() => _refreshNotificationsAsync(), delay);
+        });
+        return;
+    }
+
+    const key = String(generatedArchiveId);
+    if (archiveNotificationPollers.has(key)) {
+        return;
+    }
+
+    const pollOnce = async () => {
+        try {
+            const notificationModule = await import('./notificationStore.js');
+            await notificationModule.fetchNotifications();
+            const resolvedNotification = _findCompletedArchiveNotification(
+                notificationModule.$notifications.get(),
+                key
+            );
+            if (resolvedNotification) {
+                _clearArchiveNotificationPoller(key);
+            }
+        } catch (_) {
+            // silent — korisnik će i dalje vidjeti toast ili ručno osvježiti notifikacije
+        }
+    };
+
+    const intervalId = window.setInterval(() => {
+        void pollOnce();
+    }, ARCHIVE_NOTIFICATION_POLL_INTERVAL_MS);
+    const timeoutId = window.setTimeout(() => {
+        _clearArchiveNotificationPoller(key);
+    }, ARCHIVE_NOTIFICATION_POLL_TIMEOUT_MS);
+
+    archiveNotificationPollers.set(key, { intervalId, timeoutId });
+    void pollOnce();
+}
+
 export async function downloadWorkOrderPdf(workOrderId) {
     if (!workOrderId) {
         throw new Error('Work order ID je obavezan.');
@@ -1030,7 +1097,7 @@ export async function downloadMonthlyServiceTasksArchive(year, month) {
             return payload;
         }
         showToast('ZIP arhiva servisnih taskova se generira u pozadini. Preuzimanje je dostupno kroz notifikaciju.', 'info');
-        _schedulePdfNotificationPolling();
+        _scheduleArchiveNotificationPolling(payload?.generated_archive_id || null);
         return payload;
     } catch (err) {
         showToast(err?.message || 'Pokretanje generiranja ZIP arhive servisnih taskova nije uspjelo.', 'error');
@@ -1047,7 +1114,7 @@ export async function downloadMonthlyWorkOrdersArchive(year, month) {
             return payload;
         }
         showToast('ZIP arhiva putnih naloga se generira u pozadini. Preuzimanje je dostupno kroz notifikaciju.', 'info');
-        _schedulePdfNotificationPolling();
+        _scheduleArchiveNotificationPolling(payload?.generated_archive_id || null);
         return payload;
     } catch (err) {
         showToast(err?.message || 'Pokretanje generiranja ZIP arhive putnih naloga nije uspjelo.', 'error');