Fix cleanup wiping posters on API failure; bump deps sync_radarr/sync_sonarr now return (expected, ok) and cleanup() is skipped when either fetch failed, preventing accidental deletion of poster folders on transient API errors. Also removed the unused format_date helper and bumped requests/Pillow. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>