Capture Current webpage as Image file and save into folder at server

You can't.
It appears to work in development because the client and the server are the same computer: so copying from the screen is possible.
If it worked in production, you would not get an image of the client display, you would get an image of the server display, which will not show any web pages.

And exactly what you would get would depend on what browser the client is using to display the webpage!

You cannot access the client screen for security reasons in 99.999% of cases - the exception being IE only, ActiveX controls allowed, ActiveX controls enabled - and since the last two are disallowed by default, and IE is a "minority" browser these days, you will almost certainly not be able to do this.

Think about it: if you could do it, so could malicious sites that want to track what you do, how you access your bank account, ...