feat: implement stale client removal after timeout

- add goroutine to remove stale clients from the connection pool
- update client struct to track `LastPong` time
- set write deadline for websocket connections
- move package variables and const to `vars.go`
- log additional information when broadcasting errors

🤖

internal/websocket/broadcast.go

@@ -12,6 +12,7 @@ import (
 // Sends continous messages to all connected WebSocket clients
 func SendPermanentBroadCastMessage() {
 	tick := time.NewTicker(time.Second)
+
 	for {
 		// Marshal the message into JSON format
 		jsonMessage, err := json.Marshal(shared.State)
@@ -19,14 +20,16 @@ func SendPermanentBroadCastMessage() {
 			helper.Logger.Error("Error marshalling message:", "msg", err)
 			return
 		}
+
 		// Iterate over all connected clients and broadcast the message
 		for _, client := range Clients {
+			// Send message to client
 			err := client.SendMessage(websocket.TextMessage, jsonMessage)
 			if err != nil {
-				helper.Logger.Error("Error broadcasting to client:", "msg", err)
-				// The client is responsible for closing itself on error
+				helper.Logger.Error("Error broadcasting to client:", "msg", err, "host", client.RealIP, "clients", len(Clients))
 			}
 		}
+
 		<-tick.C
 	}
 }