Thank you for the PR! :)
I really appreciate it, but I think this implementation is not usable or too limited for many users. In many cases you want to use different project filters and configurations for different servers which is not possible with the current implementation.

My proposal would be that you can define servers like this:

servers:
  - host: gitlab.example.org
    token: abcdef123456

And then the projectConfig key is prepended by the server's host. e.g.

projectConfig:
  gitlab.example.org/john.doe/project-x:
    ...

Additionally, it should be possible to set a different config key so users can add the same server multiple times (e.g. to show projects from different users):

servers:
  - host: gitlab.example.org
    name: gitlab1
    token: abcdef123456
  - host: gitlab.example.org
    name: gitlab2
    token: ghijkl789026

projectConfig:
  gitlab1/john.doe/project-x:
    ...
  gitlab2/someone.else/project-y:
    ...