Group chat (create, manage, send messages)

[mrsumanbiswas]

Implement group conversations.

Backend

• Create groups and group_members tables
• Endpoints: POST /api/groups (create), GET /api/groups, POST /api/groups/:id/members (add member), DELETE /api/groups/:id/members/:userId (remove member)
• Group messages: POST /api/groups/:id/messages, GET /api/groups/:id/messages
• WebSocket: join a group room, broadcast messages to all online members

Frontend

• UI to create a group (select contacts, set group name/avatar)
• Group info screen (member list, add/remove)
• Chat screen adapted to show sender name and handle group message delivery
• Real‑time updates via WebSocket

Start with basic features; advanced admin controls can come later.