Features
- add TICKET_RESOLVED to WhatsAppTemplateType enum
- add Ticket Resolved WhatsApp template to admin tester page
- add wa_ticket_resolved handler with sample data to tester API
- send WhatsApp notification on ticket resolve with template fallback
- add missing webhook message types for audio, video, sticker, reaction, button, interactive
- add optimistic update for sent messages so they appear instantly
- add rich message type rendering with icons for photo, video, audio, document
- add sendTicketResolved method and auto-truncate all template params to 100 chars
- add TICKET_RESOLVED template type, name mapping, and data interface
- extract content from all webhook message types instead of storing null
Bug Fixes
- accept PDF files by extension fallback on client-side validation
- validate PDF by extension and magic bytes, not just MIME type
- add null guards for assignedBy and nullable name fields on detail page
- make firstName/lastName and assignedBy nullable in detail hook types
- default status filter to Open instead of All
- exclude reactions from conversation previews and show proper media labels
- filter reaction events from message list since they are metadata
- remove unnecessary slice on last message preview in conversation list