The two implementations of ServiceEntryPoint, ServiceEntryPointShardRole and ServiceEntryPointRouterRole, perform many of the same tasks and have very similar looking code, but are in fact mostly distinct. This leads to situations where the same change needs to be made twice or, worse, sometimes only gets made in one of the implementations despite being needed in both. We should try to share code between the two implementations more, and separate out the bits that are truly distinct between the two and unique to the role associated with the implementation.