Merging the Service Info API into the Owner Onboarding Server

[7flying]

Discussed in https://github.com/orgs/fdo-rs/discussions/572

^{Originally posted by 7flying October 23, 2023}
This issue is simply to discuss the pros and cons of having the Service Info API server implementation decoupled from the Owner Onboarding server.
Should we merge them? Should we leave them as they are?

[7flying]

The only FSIM that we need to make sure that works is the devmod fsim: https://fidoalliance.org/specs/FDO/FIDO-Device-Onboard-PS-v1.1-20220419/FIDO-Device-Onboard-PS-v1.1-20220419.html#the-devmod-module