✨ feat: Implement backend logic for screen sharing

Added WebSocket and WebRTC integration to enable screen sharing functionality in the live class routes. This implementation ensures that only authenticated users can start and view screen shares, leveraging the existing WebSocket setup for real-time communication. Key frame dispatching, ICE candidate handling, and SDP negotiation are correctly managed to support robust screen sharing sessions.

Related issue: #80

main.go

@@ -837,5 +837,6 @@ func setupLiveClassRoutes(router *gin.Engine) {
 	{
 		live.GET("screen-share/start", gin.WrapF(startScreenSharingHandler))
 		live.GET("screen-share/stop", gin.WrapF(stopScreenSharingHandler))
+		live.GET("/ws", gin.WrapF(websocketHandler))
 	}
 }