- Add go-nanoid to generate 6-char per-connection IDs; fallback to RemoteAddr
- Introduce sanitizeUsername with rules: [A-Za-z0-9_.-], spaces→_, trim ._-, max 12 chars
- Support /name <username> to change username with validation and broadcast [rename]
- Greet client with default username user_<id> and usage hint for /name
- Broadcast joins/leaves and messages including username and ID; exclude self on join
- Handle /quit to trigger unified leave flow; consistent leave announcement
- Comment/document broadcast struct, Hub, and startTCPServer
- Increase scanner buffer and add newline-delimited send in broadcaster
Client/main:
- Add flags: -host (default "localhost:9000") and -server (run only server)
- When -server is set, startTCPServer(host) and exit
- Use provided host for client connection
- Center header with width-aware lipgloss styling; adjust padding
Server:
- Introduce broadcast struct {text string, exclude net.Conn}
- Hub.msgCh now chan broadcast; send messages with optional exclusion
- On join: send “[join] …” to others (exclude the joiner)
- Broadcast chat lines without exclusion; newline-delimited as before
- Handle “/quit” by breaking loop (graceful disconnect)
- On leave: broadcast “[leave] …” to all
Refactor notes:
- Remove unconditional embedded server from client startup
- Scanner loop unchanged aside from quit handling and broadcast usage
