Reliable Background Task Scheduling on Aggressive OEM ROMs (Vivo OriginOS)

Developer is seeking solutions for reliably scheduling background tasks, specifically for an open-source app that changes wallpapers at user-defined intervals. The app functions correctly on standard Android but fails on aggressive OEM ROMs like Vivo OriginOS when the app is closed. Attempts with WorkManager, AlarmManager (setExactAndAllowWhileIdle, setAlarmClock), and BroadcastReceivers with PARTIAL_WAKE_LOCK have been unsuccessful. The core issue appears to be aggressive process killing by OriginOS, preventing alarm delivery. The developer is asking for insights into potential Vivo/OPPO/Xiaomi-specific APIs or workarounds, or if a persistent foreground service is the only viable option for tasks requiring 15-60 minute intervals on such devices.