Does it have anything to do with
Jenkins - if you stop / don't run Jenkins, do you still get just a white screen when you run your own webapp, or does it then work?
Tomcat has a number of log files in the 'logs' directory. Have a look in those log files if you can find error messages there that might give a hint about what's wrong.
It looks like you are running a
JSF application. Tomcat by default does not have support for JSF, you'll need to add the appropriate libraries and configuration to make it work.