* [relay] Replace net.Conn with context-aware Conn interface for relay transports
Introduce a listener.Conn interface with context-based Read/Write methods,
replacing net.Conn throughout the relay server. This enables proper timeout
propagation (e.g. handshake timeout) without goroutine-based workarounds
and removes unused LocalAddr/SetDeadline methods from WS and QUIC conns.
* [relay] Refactor Peer context management to ensure proper cleanup
Integrate context creation (`context.WithCancel`) directly in `NewPeer` and remove redundant initialization in `Work`. Add `ctxCancel` calls to ensure context is properly canceled during `Close` operations.
Health-check connections now send a properly formatted auth message
with a well-known peer ID instead of immediately closing. The server
recognizes this peer ID and handles the connection gracefully with a
debug log instead of error logs.
- Clients now subscribe to peer status changes.
- The server manages and maintains these subscriptions.
- Replaced raw string peer IDs with a custom peer ID type for better type safety and clarity.
* Move the handshake logic to separated struct
- The server will response to the client after it ready to process the peer
- Preload the response messages
* Fix deprecated lint issue
* Fix error handling
* [relay-server] Relay measure auth time (#2675)
Measure the Relay client's authentication time
