Add duplicate checking in handleSuccessfulFetch() to ensure one prefetch
creates at most one notification per scheduled time. This prevents prefetch
from creating duplicate notifications when a manual notification already
exists for the same time.
- Check existing notifications before saving prefetch-created content
- Skip notification creation if duplicate found (within 1 minute tolerance)
- Add null check for fetcher in scheduleBackgroundFetch() with error logging
- Log skipped duplicates for debugging
Ensures one prefetch → one notification pairing and prevents duplicate
notifications from firing at the same time.
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