Claim pending rows atomically and serialize the sidecar poller so overlapping polls cannot send the same reply twice; also stop inbound queue delivery from falling through to a second enqueue.
Co-authored-by: Cursor <cursoragent@cursor.com>
Track send attempts and schedule retry windows for pending WhatsApp outbound messages, then mark as failed after max retries to avoid silent drops without infinite resend loops.
Co-authored-by: Cursor <cursoragent@cursor.com>
