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

🤖

pkg/models/client.go

@@ -1,9 +1,9 @@
 package models
 
 import (
-	"github.com/gorilla/websocket"
+	"time"
 
-	"git.smsvc.net/pomodoro/GoTomato/internal/helper"
+	"github.com/gorilla/websocket"
 )
 
 // Represents a command from the client (start/stop)
@@ -15,17 +15,13 @@ type ClientCommand struct {
 
 // Represents a single client
 type WebsocketClient struct {
-	Conn   *websocket.Conn
-	RealIP string
+	Conn     *websocket.Conn
+	LastPong time.Time
+	RealIP   string
 }
 
 // Sends a message to the websocket.
-// Automatically locks and unlocks the client mutex, to ensure that only one goroutine can write at a time.
 func (c *WebsocketClient) SendMessage(messageType int, data []byte) error {
-	err := c.Conn.WriteMessage(messageType, data)
-	if err != nil {
-		helper.Logger.Error("Error writing to WebSocket:", "msg", err)
-		c.Conn.Close() // Close the connection on error
-	}
-	return err
+	c.Conn.SetWriteDeadline(time.Now().Add(TIMEOUT * time.Second))
+	return c.Conn.WriteMessage(messageType, data)
 }