Send and manage WhatsApp messages via WAHA HTTP API. Use when the user wants to send WhatsApp messages (text, image, video, voice, file), read chats/messages, manage contacts, groups, or sessions. Triggers on: 'send a WhatsApp message', 'check my WhatsApp chats', 'send image on WhatsApp', 'WhatsApp group', 'WhatsApp session', or any WhatsApp-related task.