feat(worker): add prefetch scheduling to reschedule logic

When a notification is displayed and rescheduled for the next occurrence,
now also schedule a background fetch to prefetch content 5 minutes before
the next notification time.

- Add DailyNotificationFetcher import to DailyNotificationWorker
- In scheduleNextNotification(), after successfully scheduling notification,
  calculate fetch time (5 minutes before next scheduled time)
- Create DailyNotificationFetcher instance and schedule prefetch
- Add logging with DN|RESCHEDULE_PREFETCH_SCHEDULED tag for observability
- Fall back to immediate fetch if fetch time is in the past

This ensures the prefetch → cache → schedule → display pipeline continues
for subsequent notifications, not just the initial scheduling.

android/plugin/src/main/java/com/timesafari/dailynotification/DailyNotificationWorker.java

@@ -32,6 +32,7 @@ import java.util.concurrent.ConcurrentHashMap;
 
 import com.timesafari.dailynotification.storage.DailyNotificationStorageRoom;
 import com.timesafari.dailynotification.entities.NotificationContentEntity;
+import com.timesafari.dailynotification.DailyNotificationFetcher;
 
 /**
  * WorkManager worker for processing daily notifications
@@ -512,6 +513,36 @@ public class DailyNotificationWorker extends Worker {
                 // Log next scheduled time in readable format
                 String nextTimeStr = formatScheduledTime(nextScheduledTime);
                 Log.i(TAG, "DN|RESCHEDULE_OK id=" + content.getId() + " next=" + nextTimeStr);
+                
+                // Schedule background fetch for next notification (5 minutes before scheduled time)
+                try {
+                    DailyNotificationStorage storageForFetcher = new DailyNotificationStorage(getApplicationContext());
+                    DailyNotificationStorageRoom roomStorageForFetcher = new DailyNotificationStorageRoom(getApplicationContext());
+                    DailyNotificationFetcher fetcher = new DailyNotificationFetcher(
+                        getApplicationContext(),
+                        storageForFetcher,
+                        roomStorageForFetcher
+                    );
+                    
+                    // Calculate fetch time (5 minutes before notification)
+                    long fetchTime = nextScheduledTime - TimeUnit.MINUTES.toMillis(5);
+                    long currentTime = System.currentTimeMillis();
+                    
+                    if (fetchTime > currentTime) {
+                        fetcher.scheduleFetch(fetchTime);
+                        Log.i(TAG, "DN|RESCHEDULE_PREFETCH_SCHEDULED id=" + content.getId() + 
+                                  " next_fetch=" + fetchTime + 
+                                  " next_notification=" + nextScheduledTime);
+                    } else {
+                        Log.w(TAG, "DN|RESCHEDULE_PREFETCH_PAST id=" + content.getId() + 
+                                  " fetch_time=" + fetchTime + 
+                                  " current=" + currentTime);
+                        fetcher.scheduleImmediateFetch();
+                    }
+                } catch (Exception e) {
+                    Log.e(TAG, "DN|RESCHEDULE_PREFETCH_ERR id=" + content.getId() + 
+                              " error scheduling prefetch", e);
+                }
             } else {
                 Log.e(TAG, "DN|RESCHEDULE_ERR id=" + content.getId());
             }