WhatsApp: inbound media + 15s live refresh
WhatsApp: document message templates (reply after the 24h window)
WhatsApp: Test button now covers reachability + inbound simulation
WhatsApp: note the per-channel Test connection button
WhatsApp: Graph API version is now a form field, not a DB edit
WhatsApp: Cloudflare Tunnel for firewalled installs + Meta Cloud API setup
WhatsApp: note the Public base URL setting
Add WhatsApp channel page + sidebar link