How to add a button in workitem in ccm with serverside plugin?
Accepted answer
https://github.com/jazz-community has several examples of UI contributions.
https://jazz.net/wiki/bin/view/Main/ContributingAttributePresentationsV2 shows some techniques.
The answers of https://jazz.net/forum/questions/62801/contributing-a-web-action-how-to-deploy could be of interest.