Complete guide for the view-once (visualização única) feature:
- Send examples (curl) for image, video and audio
- Webhook payload structure with key.isViewOnce detection
- JavaScript helpers to identify and access view-once media
- Frontend/CRM rendering guide with placeholder after open
- Implemented code with inline explanations
- Full send/receive flow diagram
- Known limitations and validation checklist
Co-Authored-By: Renato Alcara