🐛 [Streaming Chat] Improve error handling on bad chat request messages

[roma-glushko]

A Glide's streaming channel gets closed on chat requests that doesn't pass validation.
The issue is in the way we handle errors right now:

glide/pkg/api/http/handlers.go

Lines 139 to 148 in bca8c8f

	if err = c.ReadJSON(&chatRequest); err != nil {
	// TODO: handle bad request schemas gracefully and return back validation errors
	if websocket.IsUnexpectedCloseError(err, websocket.CloseNormalClosure, websocket.CloseGoingAway) {
	tel.L().Warn("Streaming Chat connection is closed", zap.Error(err), zap.String("routerID", routerID))
	}
	tel.L().Debug("Streaming chat connection is closed by client", zap.Error(err), zap.String("routerID", routerID))
	break
	}

For example, you can open a streaming chat connection (via Postman, for example):

{{base_url}}/language/{{routerID}}/chatStream

Then, send it just an empty message like:

{
  
}

You would get an error like:

Finally, if you try to send a valid message now:

"message": {
    "role": "user",
    "content": "Write an essay about ecommerce in a modern era"
  }

It would not really work.