Inconsistent use of the ILinkProvider interface

[bsstahl]

There are places in the code that generate their own URLs rather than using the ILinkProvider service. It is important to use the service so that the implementation of links remains consistent throughout the project and can be swapped-out with a more professional library (like Flurl perhaps) down the road.

We need to find everywhere in the code where a URL is generated that does not use the ILinkProvider to do so, and fix it.