Mock SIWF v2 Service

[wilwade]

We want to deprecate the SIWF v1 paths, but to do that, we need a way to use SIWFv2 on local only.

Note: This might need to move to the SIWF repo

That means we need a service that is a mock/local version that meets the SIWFv2 spec.

• Allows selection and creation of mock users
  • Should generate some default set based on a base key, but also generation of new ones
  • Suggested: //Alice or //SiwfMock and the a derived path, but outside of the default derived paths, you can add your own.
• Should be easy to configure / no config needed
• Dockerized and local
• Should do the authorizationCode redirect
• Should also be able to have a flag in the additional url params to auto select and redirect for a particular user (for automated tests)