Hono-based API server with LastLogin authentication, SQLite database, and group chat functionality.

• index.ts - Main HTTP handler with LastLogin wrapper
• database/ - Database migrations and query functions
• routes/ - API route handlers

• All API routes require authentication via LastLogin
• User email is extracted from X-LastLogin-Email header

• GET /api/conversations - Get user's conversations (with participant info)
• GET /api/conversations/:id - Get specific conversation with messages
• POST /api/conversations - Create new conversation
• DELETE /api/conversations/:id - Delete conversation (admin only)

• GET /api/conversations/:id/participants - Get conversation participants
• POST /api/conversations/:id/invite - Invite user by email (admin only)
• DELETE /api/conversations/:id/participants/:userId - Remove participant (admin only)

• GET /api/invites/:token - Get invitation details (public)
• POST /api/invites/:token/accept - Accept invitation and join conversation

• POST /api/chat - Send message and get ChatGPT response
• GET /api/conversations/:id/stream - Server-Sent Events for real-time updates

• chat_users_v1 - User accounts
• chat_conversations_v1 - Conversation metadata
• chat_messages_v1 - Individual messages

• conversation_participants_v1 - User-conversation relationships with roles
• conversation_invites_v1 - Pending email invitations with tokens

• Automatic user creation on first login
• Conversation history storage with full message history
• ChatGPT integration via OpenAI API
• Group chat functionality with role-based permissions
• Email invitations with secure tokens
• Real-time updates via Server-Sent Events
• Secure user isolation - users can only access their conversations