feat: introduce vars.go for websocket package

- update comments
- move `Done` variable to vars.go
- move `Connected()` method

🤖

internal/websocket/receive.go

@@ -9,8 +9,6 @@ import (
 	GoTomato "git.smsvc.net/pomodoro/GoTomato/pkg/models"
 )
 
-var Done = make(chan struct{})
-
 // Receives websocket messages and writes them to a channel.
 // Closes the channel if websocket closes.
 func (c *Client) ProcessServerMessages(channel chan<- GoTomato.ServerMessage) {