Web socket

using golang.org/x/net/web-socket

Folder structure

myapp/
├── cmd/
│   └── ws/
│       └── main.go
├── internal/
│   ├── ws/                 # WebSocket-specific logic
│   │   ├── handler.go      # Upgrade + connection entry
│   │   └── message.go      # Message definitions
├── website/
│   ├── index.html # client html+js
├── go.mod
├── client.go       # Single connection abstraction